Prasanna

Students can Download Chapter 10 Internal Trade Notes, Plus One Business Studies Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Business Studies Notes Chapter 10 Internal Trade

Contents

• Internal Trade – Meaning – Types
• Whole Sale Trade – Meaning – Function – Services to producers and retailers
• Retail Trade – Meaning – functions – services to producers/wholesalers and consumers
• Types of Retail trade – Itinerant Traders – Fixed shop retailers
• Departmental Store – Meaning – Features Advantages – Limitations
• Multiple shop – Meaning – Features – Advantages Limitations
• Mail order business – Meaning – Features Advantages – Limitations
• Consumer co – operative store – Meaning Features – Advantages – Limitations
• Supermarket – Meaning – Features – Advantages Limitations
• Vending Machines – Meaning
• Role of Chamber of Commerce and Industry

Internal Trade:
Buying and selling of goods and services within the boundaries of a nation are called internal trade. Internal trade can be classified into two broad categories viz.

• Wholesale trade
• Retail trade

Wholesale Trade:
Wholesale trade means buying goods in large quantities from the producers and selling them in smaller quantities to the retailers. Wholesalers acts as an important link between manufacturers and retailers.
Functions of Wholesaler:
1. Buying and assembling:
The wholesalers buy goods from different producers and keep them in a central place.

2. Warehousing:
The goods are to be kept in the I warehouses till they are sold to retailers.

3. Grading and packing:
The goods purchased are sorted out on the basis of quality and size. This is called grading. After grading they are packed in attractive packages

4. Pricing:
The wholesaler fix the price of products

5. Transportation:
The wholesalers move the goods from the production centre to the retail shop

6. Risk bearing:
They assume the risk like change in demand, spoilage, theft during transportation etc.

7. Financing:
Wholesalers purchase goods on cash basis from manufacturers and sell them to the retailers on credit basis.

8. Market information:
Wholesalers collect various market information for the benefits of manufacturers so that they can change the products accordingly

Services of Wholesalers to Manufacturers:
1. Facilitating large scale production:
As the wholesalers place bulk orders, the producers are able to undertake production on a large scale and take advantages of economies of scale.

2. Risk bearing:
Wholesaler deals in goods in their own name and bear variety of risks such as the risk of fall in prices, theft, pilferage spoilage, fire etc.

3. Financial assistance:
Wholesalers provide financial assistance to the manufacturers by making cash payment for the purchased goods.

4. Expert advice:
Wholesaler provide various useful information regarding the customer preference, market conditions etc to the manufacturer.

5. Help in marketing function:
As the wholesalers place bulk orders, it relieves the producer from many marketing activities and he can concentrate on production.

6. Storage facilities:
Wholesalers hold the goods in their own warehouses. It reduces the burden of storage of goods by the manufacturers.

7. Facilitate production continuity:
The wholesalers facilitate continuity of production activity throughout the year by purchasing the goods as and when these are produced

Services of Wholesalers to Retailers:
1. Availability of goods:
The wholesalers make the products of various manufacturers readily available to the retailers.

2. Marketing support:
They undertake advertisements and other sales promotional activities to induce customers to purchase the goods.

3. Grant of credit:
The wholesalers generally provide credit facilities to the retailers.

4. Specialised knowledge:
Wholesalers know the pulse of the market. They inform the retailers about the new products, their uses, quality, prices, etc.

5. Risk sharing:
Wholesalers sell goods to retailers in small quantities and thus retailers do not face the risk of storage, pilferage, reduction in prices etc.

Retail Trade:
Buying of goods in large quantities from the wholesalers and selling them in small quantities to the ultimate consumers is known as retail trade. Retailers serve as an important link between the producers and consumers in the distribution of products and services.
Functions of Retailers:

1. A retailer collects different varieties of goods. So he can satisfy different types of customers.
2. A retailer provides market information to wholesalers and manufacturers.
3. A retailer is in close contact with consumers. So he can persuade the consumers to buy the product.
4. Retailers locate their business in residential areas. It helps the consumers to purchase the product easily.
5. The retailers provide credit facilities to the consumers.
6. Retailers provide after sales services to attract consumers.

Services of Retailers to Manufacturers and Wholesalers:
1. Retailers help manufacturers & wholesalers in the distribution of their goods & services to the ultimate consumers.

2. Retailers undertake personal selling efforts and thus, help manufacturers and wholesalers to increase the sale of the products.

3. Retailers help manufacturers and wholesalers to operate production on a large scale by undertaking distribution of goods.

4. As retailers are in constant touch with customers, they can provide various market information such as the tastes, preferences and attitudes etc. of consumers to the producers.

5. Retailers participate in various sales promotional activities conducted by producers and wholesalers.

Services Retailers to Consumers:

1. Retailers provide goods to consumers according to their requirements.
2. Retailers keep large varieties of products of different manufacturers. It enable the customers to select goods according to their choice.
3. Retailers provide important information about the new products to the consumers.
4. Retailers also provide after sales services in the form of home delivery etc. to the customers.
5. Retailers often supply goods on credit to the customers.
6. Retailers keep ready stock of the products needed by the consumers.

Differences between wholesaler and Retailer:

Types of Retail Trade:
Retail trade can be classified into following two categories on the basis whether or not they have a fixed place of business.

• Itinerant Retailers
• Fixed shop Retailers

Itinerant Retailers:
The retailers who do not have a fixed place of business to operate from are called itinerant retailers. They have to move from one place to another along with their goods in search of consumers.
Characteristics of itinerant retailers:

1. They are small traders having limited resources.
2. They generally deal in consumer products of daily use.
3. They emphasize on providing greater customer services.
4. They do not have any fixed place to operate from.

Types of itinerant retailers:
1. Peddlers and hawkers:
They cany the products on a bicycle, a hand cart, a cycle-rickshaw or on their heads, and move from place to place to sell their products at the doorstep of the customers. They generally deal in non-standardised and low- value products such as toys, vegetables, fruits etc.

2. Market traders:
They are the small retailer who open their shops at different places and sell the goods on fixed days such as every Saturday or Tuesday. These trader deals in single line of goods such as toys, readymade garment crockery, etc.

3. Street traders:
These traders display their articles on busy streets, bus stand, railway stations etc. They sell low priced articles like pen, books, magazines, hand kerchiefs etc. They do not change their place of business frequently.

4. Cheap jacks:
They are small retailers who have independent shops of a temporary nature in a business locality. They keep on changing their business from one locality to another but not very frequently. They deal in consumer items such as repair of watches, shoes, buckets etc.

Fixed Shop Retailers:
Retailers who maintain permanent establishment to sell their goods are called fixed shop retailers. Following are the main characteristics of fixed shop retailers.

1. They have greater resources and operate on a relatively large scale.
2. They deal in durable as well as non-durable goods.
3. They provide greater services to the customers such as home delivery, repairs, credit facilities etc.

Types of Fixed Shop Retailers:
The fixed-shop retailers can be classified into two. They are:

• Small shop-keepers
• Large retailers

Fixed Shop Small Retailers:
1. General stores:
These shops carry stock of a variety of products required to satisfy the day-to-day needs of the consumers residing in nearby localities. They deal products of daily use such as grocery items, soft drinks, Stationary etc.

2. Speciality shops:
These retail stores specialise in the sale of a specific line of products. For example, shops selling children’s garments, men’s wear, ladies shoes, toys and gifts, school uniforms etc. The speciality shops are generally located in a central place where a large number of customers can be attracted.

3. Street stall holders:
These shops are generally located at street crossings or in the main street. They usually display their goods on a table or by fixing shelf on the wall. Low priced articles such as pen, cosmetics, magazines etc. are sold in these stalls. .

4. Secondhand goods shop:
These shops deal in secondhand goods such as books, clothes, furniture, automobile etc. People who cannot afford to buy new articles, generally, becomes their customers.

Fixed shop large retailers:
Departmental stores:
A departmental store is a large scale retail shop selling a wide variety of goods in different departments under one and management. Each department deals in separate line of goods like stationary, books, furniture, clothing etc. Consumers can purchase all goods from the departmental store.
Features of a departmental store:

1. It Is a large scale retail organization.
2. A number of retail shops in the same building.
3. It offers a wide variety of products under one roof.
4. It is located at central places of the city
5. The products are arranged in separate departments
6. Sales, control and management are centralized
7. It offers various services and facilities like free home delivery etc

Advantages:

1. Central locations: As these stores are usually located at central places they attract a large number of customers
2. Convenience in buying: By offering large variety of goods under one roof, the departmental stores provide great convenience to customers in buying almost all goods of their requirements at one place.
3. Attractive services: A departmental store aims at providing maximum services to the customers.
4. Economy of large-scale operations: As these stores are organised in a very large-scale, the benefits of large-scale operations are available to them
5. Mutual advertisement:-All the departments are under one roof, so there is economy in advertising
6. Risk distribution: If there is a loss in one department, it may be compensated from the profit of other departments
7. Increased sales: Central location, mutual advertisement etc. will help a departmental store to increase its sales.

Limitations:
1. Lack of personal attention:
Because of the large- scale operations, it is very difficult to provide adequate personal attention to the customers in these stores.

2. Inconvenient location:
As a departmental store is generally situated at a central location, it is not convenient for the consumers who reside away from town.

3. High price:
A departmental store charges high price for the products because of high operating cost.

4. High operating cost:
As these stores give more emphasis on providing services, their operating costs tend to be high.

5. High advertisement cost:
The success and prosperity of a departmental store depends on advertisement. Therefore, it should spent large amount on advertisement.

6. Lack of effective control:
Departmental store works through a large number of departments. It creates so many problems.

7. High risk:
A departmental store keeps a large stock of goods. So changes in fashion, taste, price etc will affect the profitability of the business.

Chain Stores or Multiple Shops:
Multiple shop is a system of branch shops operated under a centralised management and dealing in similar line of goods. Branches are located through out the nation.
Features of multiple shops:

1. It deals in one or two lines of products.
2. All branches are dealing in similar goods
3. It has centralized management and unified system of control
4. It eliminates middlemen.
5. It works on cash and carry principle
6. It has centralized buying and decentralized selling.
7. There is uniformity in operation in all branches.
8. It deals in goods of daily use and durables.

Advantages:

1. It enjoys economies of bulk purchase because the goods for all branches are purchased by head office.
2. There is no risk of bad debts because all sales are on cash basis.
3. The advertisements for all branches are done by the head office. So there is economy in advertisement.
4. Multiple shops are located in towns and cities. They attract a large number of customers.
5. All branches of multiple shops are uniform in style, design and display of goods.
6. All the branches sell quality goods at uniform prices. It creates public confidence.
7. The economy in large scale buying, centralized management, etc. reduce the cost of operations.
8. Products having no demand in one branch can be transferred to another branch. It reduces business risk.
9. Multiple shops enjoy the benefits of quick turn over because of country wide location.

Limitations:

1. The multiple shops deal only in a limited range of products. So consumers have very little choice.
2. They will not provide any credit facilities to consumers.
3. There is lack of personal touch between the company and consumers because branches are managed by salaried managers.
4. Branch manager is only a salaried employee. He has no initiative to increase the profits.
5. As these shops deal in a limited line of goods, fall in demand will affect the business.

Difference between Departmental stores and Multiple shops:

Mail Order Houses/shopping by Post:
Mail order business is a form of retailing where the business transactions are done through post or mail. Under this system orders for goods, delivery of goods and payment is made through VPP (Value Payable Post).

Under this arrangement, the goods are delivered to the customers only on making full payment for the same. There is generally no direct personal contact between the buyers and the sellers in this type of trading.
This type of business is suitable for products that can be:

1. graded and standardised
2. easily transported at low cost
3. have ready demand in the market
4. are available in large quantity throughout the year
5. involve least possible competition in the market
6. can be described through pictures.

Bulky, heavy and perishable products are not suitable for this type of business.
Advantages:

1. It needs only limited capital because there is no need of building and other infra structural facilities.
2. Unnecessary middlemen between the buyers and sellers are eliminated.
3. Since the mail order houses do not extend credit facilities to the customers, there are no chances of any bad debt.
4. Under this system goods are delivered at the doorstep of the customers. This results in great convenience to the customers.
5. There is a wider scope for business.
6. It helps to avoid overstocking of goods as goods are collected only when the orders are received.

Disadvantages:

1. It has to spend a large amount for advertisement.
2. There is no direct personal contact between the buyer and the seller.
3. The buyer qannot inspect the goods personally before purchasing.
4. They are not suitable for heavy and perishable goods.
5. They do not provide credit facilities to customers.
6. There may be delay in getting goods.

Consumer Cooperative Store:
It is a retail store formed by the consumers on the basis of principles of co-operation. Thses stores are owned and managed by consumers. They deal all types of consumer goods.
Features of Consumers Co-operative:

1. It is a voluntary association of consumers.
2. The liability of members is limited.
3. Consumers can purchase quality goods at lowest cost from these stores.
4. Democratic control is exercised.
5. It eliminates middlemen

Advantages:

1. Consumers can purchase quality goods at lowest cost from consumers co-operative store.
2. There is no bad debts as goods are sold on cash basis.
3. Economies of large scale purchasing can be enjoyed.
4. Less advertisement expenses are required.
5. It restricts monopoly and wasteful competition.

Disadvantages:

1. A consumer co-operative store can collect low capital. So they cannot start business on a large scale.
2. The management of a consumer co-operative store is inefficient.
3. It lacks proper warehousing facilities.
4. It will not attract consumers because of no credit facilities.

Supermarkets/Super Bazaar:
Supermarket is a large scale retail organisation selling a wide variety of consumer goods. The important feature of supermarket is the absence of salesman to help consumers in selecting goods. Hence supermarket is also called ‘Self Service Store’.
Features of Super Market:

1. They are located at the centre of a town.
2. They sell goods on cash basis only.
3. They deal wide variety of goods.
4. There is no salesman to help consumers

Advantages:

1. Consumers can purchase everything from supermarket
2. There is no bad debt as sales are on cash basis only.
3. They are located at the centre of a town.
4. It attracts a large number of consumers.
5. Consumers can select goods according to their taste and preferences.
6. Variety of goods is available in a supermarket.

Disadvantages:

1. Large premises at central location is not available easily.
2. It lacks personal advice of salesman
3. They do not provide credit facilities to customers.
4. The employees in a supermarket do not take initiative to increase sales.
5. It requires huge capital investment.
6. It is not suitable for products which require personal selling.
7. There is no personal contact with consumers.

Vending Machines:
They are coin operated machines which are used in selling several products such as milk, soft drinks, chocolates, platform tickets etc in many countries. The latest area in which this concept is getting popular is the cpse of Automated Teller Machines (ATM) in the banking service.

However, the installation cost and expenditure on regular maintenance and repair of these machines are quite high. Moreover, the consumers can neither see the product before buying nor can return the unwanted goods.

Role of Chambers of Commerce and Industry in Promotion of Internal Trade:
Association of business and industrial houses are formed to promote and protect their common interest and goals. They undertake following functions.

1. The chamber of commerce and Industry help in the inter-state movement of goods through various activities.
2. They ensure that imposition of octroi and other local taxes do not affect trade adversely.
3. They also undertake marketing of agro products and related issues.
4. They interact with the Government to make laws relating to weights and measures and protection of brands.
5. They discuss with government to get sound infrastructure so that business activities could be undertaken easily

Students can Download Chapter 9 Small Business Notes, Plus One Business Studies Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Business Studies Notes Chapter 9 Small Business

Contents

• Small business – Meaning and Nature – administrative setup – Role of Small Business in India – Problems of Small Business
• Government assistance to small industries- Institutional support
• NABARD
• RSBDC
• NSIC
• SIDBI
• NCEUS
• RWED
• WASME
• SFURTI
• DIC
• Government assistance to small industries – Incentives

Types of Small business units in India:
On the basis of the capital invested, small business units can be categorized into various categories.
They are:
1. Small scale industry:
A small scale industrial undertaking is defined as one in which the investment in fixed assets of plant and machinery does not exceed rupees one crore.

2. Ancillary small industrial unit:
An ancillary industrial unit is one which supplies not less than 50% of its output to another parental unit. It can manufacture parts, components, subassemblies, tools or intermediate products for the parent unit. Also it can do business on its own.

3. Export oriented units:
Export-Oriented unit is one which exports more than 50% of its output and wherein investment in plant and machinery does not exceed rupees one core.

4. Small scale industries owned and managed by women entrepreneurs:
An enterprise promoted by women entrepreneurs is a small scale industrial unit in which she/they individually or jointly have share capital of not less than 51 percent. Such units gets concessions offered by the government, like low interest rates on loans, etc.

5. Tiny Industrial Unit:
A tiny unit is defined as an industrial or business enterprise whose investment in plant and machinery is not more than ₹ 25lakhs.

6. Small scale service and business enterprise:
It is one whose investment in fixed assets of plant and machinery excluding land and building does not exceed ₹ 10 lakhs.

7. Micro business enterprises:
Micro enterprises are those whose investment in plant and machinery does not exceed rupees one lakh.

8. Village industries:
Village Industry has been defined as means any industry located in a rural area which produces any goods, renders any service with or without the use of power and in which fixed capital investment per head does not exceeds ₹ 50,000.

9. Cottage industries:
cottage industries are characterised by certain features

• These are organised by individuals, with private resources;
• Normally use family labour and locally available talent;
• The equipment used is simple
• Capital investment is small
• Produce simple products, normally in their own premises;
• Production of goods using indigenous technology.

Administrative setup for the Small scale, Agro and Rural Industries:
For the promotion and development of small scale industries in India, Government created two ministries, i.e
1. Ministry of Small Scale Industries:
The Ministry of Small Scale Industries designs policies, programmes, and schemes for the promotion and growth of SSIs. The Small Industries Development Organisation (SIDO) is responsible for implementing and monitoring of various policies and programmes formulated.

2. Ministry of Agro and Rural Industries:
Ministry of Agro and Rural Industries is the nodal agency for coordination and development of Village and Khadi industries, tiny and micro enterprises in both urban and rural areas.

Various programs and policies are implemented by the ministry through the Khadi and Village Industries Commission (KVIC), Handicrafts Board, Coir Board, Silk Board etc.

State Governments also provide different promotional and developmental projects and schemes to provide a number of supporting incentives for development and promotion of SSIs. These are executed through the State Directorate of Industries and District Industries Centres (DICs).

Role of small business in India:

1. Small industries are labour intensive and less capital intensive. They generate more number of employment opportunities.
2. The share of product from small industries is 45% of total export from India. So it earn valuable foreign exchange
3. Small scale Industries produces a wide variety of goods e.g. readymade garments, stationery, soaps, leather goods, plastic and rubber goods.
4. The contribution of small industries to the balanced regional development of the country is very significant.
5. Small industries provide ample opportunity for entrepreneurship.
6. It enjoys the advantage of low cost of production because they used local resources in their product.
7. Due to the small size of the organisation, quick and timely decisions can be taken without consulting many people.
8. Small industries are best suited for the products which are designed according to the taste, needs and preferences of the customers.
9. Small industries maintain good personal relations with both customers and employees.

Role of small business in Rural India:

1. Cottage and rural industries provide employment opportunities in the rural areas especially for the traditional artisans and the weaker sections of society.
2. It prevents migration of rural population to urban areas in search of employment.
3. Small business helps to eradicate poverty, income inequalities etc in rural area.
4. Small scale industries are powerful instrument for the accelerated industrial growth and creating productive employment in rural and backward areas.

Problems of small business:
Small businesses are faced with the following problems.

1. Small scale industries find it difficult to get adequate finance from banks and other financial institutions.

2. They are not able to get quality raw materials at reasonable prices.

3. Small business is generally operated by people who may not have all the managerial skills required to run the business.

4. Small business firms cannot afford to pay higher salaries to the employees. So productivity per employee is relatively low and employee turnover is generally high.

5. Small business depends excessively on middlemen for marketing the products. Middlemen exploit them by paying low price and delayed payments.

6. Small business organization uses out dated technology to produce products. So they cannot compete with global enterprises with low quality products.

7. Due to lack of marketing skills or lack of demand, many small business firms have to operate below full capacity.

8. Use of outdated technology results low productivity and uneconomical production.

9. Small-scale units find it very difficult to compete .with the product of multinational companies which are comparatively very cheap and of better quality

10. Other important problems are poor project planning, inefficient management, transportation problems, lack of power, and lack of adequate warehousing, etc.

Government assistance to small Industries and Small Business:
A. Institutional Support:
1. National Bank for Agriculture and Rural Development (NABARD):
NABARD was set up in 1982 to promote integrated rural development.
Functions of NABARD:

• It provides financial support to small Industries, cottage and village industries and agriculture.
• It provides counseling and consultancy services.
• It also organises training and development programme for rural entrepreneurs.

2. The Rural Small Business Development Centre (RSBDC:
It aims at providing management and technical support to current and prospective micro and small entrepreneurs in rural areas. RSBDC has organized several programmes on rural entrepreneurship, skill upgradation workshops, training programmes etc.

3. National small Industries Corporation (NSIC):
This was set up in 1955 to promote, aid and foster the growth of small scale units in India.
Functions of NSIC:

• It supplies imported machines and raw materials to small scale industries on easy hire-purchase schemes.
• It exports the products of small units.
• It provides technology to small scale Industries.
• Helps in up-gradation of technology
• Provides advisory service
• Developing software technology parks and technology transfer centres.

4. Small Industries Development Bank of India (SIDBI):
SIDBI was set up in 1980. SIDBI is the main financial Institution for financing and development of small Business in India.
Functions of SIDBI.

• Helps SSI unit for modernisation and technology upgradation by providing loan
• Meet working capital requirements of SSI.
• Provides means forthe rehabilitation of sick units
• Provides service like leasing, hire purchase, venture capital financing etc.
• Provide equity support to small entrepreneurs.

5. The National Commission for Enterprises in the Unorganised Sector (NCEUS):
The NCEUS was constituted in September, 2004, with the following objectives.

• To recommend measures for improving the productivity of small enterprises
• To generate more employment opportunities in rural areas
• To enhance the competitiveness of the sector in the emerging global environment.
• To link the sector with other institutions in the areas of credit, raw materials, infrastructure, technology upgradation etc.

6. Rural and Women Entrepreneurship Development (RWED):
RWE provides the following services.

• Creating a business environment that encourages initiatives of rural and women entrepreneurs.
• Enhancing the human and institutional capacities required to foster entrepreneurial dynamism and enhance productivity.
• Providing training manuals for women entrepreneurs and training them.
• Rendering all types of advisory services.

7. World Association for Small and Medium Enterprises (WASME):
It is the only International Non-Governmental Organisation of micro, small and medium enterprises based in India, which set up an International Committee for Rural Industrialisation. Its aim is to develop an action plan model for sustained growth of rural enterprises.

There are several schemes to promote the non-farm sector initiated by the Government of India, i.e. IRDP, PMRY, TRYSEM, JRY, Development of Women and Children in Rural Areas (DWCRA) etc.

8. Scheme of Fund for Regeneration of Traditional Industries (SFURTI):
To make the traditional industries more productive and competitive, the Central Government set up a fund with ₹ 100 crores. The main objectives of the scheme are as follows:

• To develop clusters of traditional industries in various parts of the country
• To make traditional industries competitive, profitable and sustainable
• To create employment opportunities in traditional industries.

9. The District Industries Centers (DICs):
DICs were established in May 1978. District Industries Centers is the institution at the district level which provides all the services and support facilities to the entrepreneurs for setting up small and village industries.

Identification of suitable schemes, preparation of feasibility reports, arranging for credit, machinery and equipment, provision of raw materials and other extension services are the main activities undertaken by these centers.

B. Incentives:
The incentives offered by the government to develop backward areas are:

1. Availability of land at concessional rate.
2. Supply power at a concessional rate of 50% or exempt such units from payment in the initial years.
3. Water is supplied on a no-profit, no-loss basis or with 50 percent concession or exemption from water charges for a period of 5 years.
4. All union territories, industries are exempted from sales tax,
5. Most states have abolished octroi.
6. Units located in backward areas get scarce raw materials at concessional rates.
7. Subsidy of 10-15% for building capital assets. Loans are offered at concessional rates.
8. Some states encourage setting up of industrial estates in backward areas.
9. Exemption from paying taxes for 5 or 10 years is given to industries established in backward, hilly and tribal areas.

Students can Download Chapter 9 Mechanical Properties of Solids Notes, Plus One Physics Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Physics Notes Chapter 9 Mechanical Properties of Solids

Summary
Introduction
Elasticity:
The property of a material by virtue of which it regains its original shape on the removal of the deforming force is called elasticity. The deformation caused is known as elastic deformation.

Plasticity:
The property of a material by virtue of which it does not regain its original shape on the removal of the deforming force is called plasticity. The substance which shows this property is called plastic.

Elastic Behavior Of Solids
In a solid, each atoms (or molecule) is surrounded by neighboring atoms (or molecules). These atoms are bonded by inter atomic forces. When a solid is deformed, the atoms are displaced from their equilibrium positions. When the deforming force is removed, the interatomic force bring back atoms into its original position. Thus body regains its original shape and size.

Stress And Strain Stress
It is the restoring force developed per unit area of cross section

S.I unit of stress is Nm² or Pascal (Pa) and its dimensional formula is [ML^-1 T^-2]. The restoring force is equal and opposite to the external applied force.
Strain:
The effect of stress on a body is called strain. Strain is measured as the ratio of the change in dimension produced to the original dimension.

Different types of Stress and Strain:
There are three ways in which a solid may change its dimensions when an external force acts on it. Hence there are three types of stress and corresponding strain.

1. Tensile Stress and Longitudinal Strain:
When the forces acting on the body produces an elongation along its length, then we call the stress as tensile stress (see figure).

When the forces acting on the body produces a compression along its length, then we call the stress as compressive stress. The tensile stress produces a change in the length (∆L). Hence the longitudinal strain can be written as
Longitudinal strain = \(\frac{\text { Change in length }}{\text { Original length }}\)
Longitudinal strain = \(\frac{\Delta \mathrm{L}}{\mathrm{L}}\)
Where ‘L’ is the original length.

2. Tangential (or) Shearing Stress and Shearing Strain:

If two equal and opposite deforming forces are applied parallel to cross-sectional area of the cylinder as shown in figure, there is a relative displacement between the opposite faces of the cylinder. The restoring force per unit area developed due to the applied tangential force is known as tangential or shearing stress.

As a result of applied tangential force, there is a relative displacement between opposite faces of the cylinder (see figure). The strain so produced is known a shearing strain. Shearing strain can be written as,

Where θ is the angular displacement of the cylinder from the vertical (original position of the cylinder). Since θ is very small, tanθ ≈ θ.

3. Hydraulic Stress and Volume Strain:

Consider a solid placed inside the fluid. The force applied by the fluid acts in perpendicular direction at each point of the surface. This leads to decrease in its volume without any change of its geometrical shape.

The internal restoring force per unit area in this case is known as hydraulic stress. The strain produced by a hydraulic pressure is called volume strain. The volume stress can be written as
Volume strain = \(\frac{\text { Change in volume }}{\text { Original volume }}=\frac{\Delta \mathrm{V}}{\mathrm{V}}\)
Note: Hydraulic Stress is equal to the hydraulic pressure.

Hooke’S Law
Hooke’s law:
For small deformations, the stress and strain are proportional to each other, ie: stress ∝ strain. Stress = k × strain Where k is the proportionality constant and is known as modulus of elasticity.

Stress Strain Curve

A typical graph for stress – strain graph for a metal is given in the figure.
Region OA:
In the region between O to A, the curve is linear. Hence in this region Hooke’s law is obeyed. The body regains its original dimensions when the applied force is removed. In this region the material behaves as an elastic body.

Region AB:
In this region stress and strain are not proportional. The material returns to its original dimension when the applied force (stress) is removed. The point B in the curve is known as yield point (also known as elastic limit) and corresponding stress is yield strength of the material.

Region BD:
If the applied force exceeds the yield strength, strain increases rapidly for a small change in the stress. When the applied force (stress) is removed at ‘C’, the body does not regain it’s original dimension, (even when the stress is zero, the strain is not zero).

This deformation is said to be plastic deformation and the material is said to have a permanent set. The point D on the graph is the ultimate tensile strength of the material.

Region DE:
Beyond this point D, additional strain is produced even by a reduced applied force and fracture occurs at the point E. The point E is called fracture point. If the ultimate strength (D) and fracture point (E) are close, the material is said to be brittle. If they are far apart, the material is said to be ductile.

Elastomers:
For rubber like materials, even for a small stress, the strain produced will be very high. Such materials are called elastomers.

There is no plastic flow region in the curves for elastomer materials. The elastic tissues of our blood vessel (aorta) is another example for elastomer.
Note: elastomer materials do not obey Hooke’s law.

Elastic Moduli
According to Hooke’s law

where k is called modulus of elasticity.
Depending on different types of stress and strain, there are 3 types of modulus of elasticity.
Different types of modulus of elasticity

1. Young’s modulus (Y)
2. Shear modulus (G)
3. Bulk modulus (B)

1. Youngs Modulus:
Young’s modulus is defined as the ratio of tensile stress (α) to the longitudinal strain (ε).
ie; Youngs modulus Y = \(\frac{\text { tensile stress }}{\text { longitudinal strain }}\)
Y = \(\frac{\alpha}{\varepsilon}\)
Explanation:
Consider a wire of length L and area of cross section a, fixed at one end and loaded at the free end with a weight mg. Let l be the elongation. Then tensile strain α = \(\frac{F}{a}\)
Longitudinal strain ε = \(\frac{l}{L}\)

2. Determination of youngs modulus of the material of a wire:
Experimental setup:

An experimental arrangement to determine the young’s modulus of a wire is shown in the figure. It consists of two long straight wires A and B. (The wire Ais called reference wire and B is called experimental wire).

A millimeter scale (main scale) is fixed near to the wire A. At bottom of wire A there is a pan to place a weight. The wire B also carries a pan in which known weights can be placed. At bottom of wire B, there is a pointer. A vernier scale is attached to this pointer. This vernier scale of B and main scale of A are placed very close to each other.

Determination of Young’s modulus:
Keep the wires (A and B) as straight by placing sufficient load at pans and note down initial reading. Then the experimental wire (B) is loaded with more weights. Note down the reading again. The difference between initial reading and final reading gives the elongation.

Let rand L be the initial radius and length of the experimental wire, then the area of cross section of the wire is πr². Let µ be the mass that
produced an elongation ∆L in the wire.

3. Shear Modulus:

The ratio of shearing stress to the corresponding shearing strain is called the shear modulus of the material (represented by G). It is also called the modulus of rigidity.

But from figure tanθ = \(\frac{\Delta x}{L}\) = tanθ ≈ θ
∴ G = \(\frac{F}{A \theta}\) The shearing stress α_s can also be expressed as α_s = Gθ.

4. Bulk modulus (B):
When a body is immersed in a fluid, it undergoes a hydraulic stress (equal in magnitude to the hydraulic pressure.) This leads to the decrease in the volume of the body. This decrease in volume produces a strain is called volume strain.

The ratio of hydraulic stress to the corresponding hydraulic strain is called the bulk modulus. It is denoted by symbol B. ie; Bulk modulus

The minus sign indicates the fact that with an increase in pressure, a decrease in volume • occurs. S.l. unit of bulk modulus is the same as that of pressure ie; Nm^-2 (or) Pa.
Compressibility (k):
The reciprocal of the bulk modulus is called
compressibility, k = \(\frac{1}{B}\)
Note: Bulk modulus of solids > Bulk modulus of liquid > Bulk modulus of gases.

Question 1.
Solids are least compressible but gases are most compressible. Why?
Answer:
The molecules in solids are strongly coupled with neighboring atoms. But molecules in gases are very poorly coupled to their neighbors.

5. Poisson’S Ratio
When a wire is subjected to an extension along its length there will be contraction perpendicular to the length. The strain perpendicular to the applied force is called lateral strain. The strain parallel to the applied force is called longitudinal strain.

Within the elastic limit, lateral strain is directly proportional to the longitudinal strain. The ratio of the lateral strain to the longitudinal strain is called Poisson’s ratio.

If the original diameter of the wire is d and the contraction of the wire under stress is Dd, lateral strain = \(\frac{\Delta \mathrm{d}}{\mathrm{d}}\)
If the original length of the wire is L and the elongation under stress is DL, then

Poisson’s ratio is a ratio of two strains. Hence it is a pure number and has no units or dimensions.
For steel the value is between 0.28 and 0.30.

6. Elastic potential energy in a stretched wire:
When a wire is stretched, work is done against the inter molecular forces. This work is stored in the wire as elastic potential energy.

Consider a wire of length L and area of cross section stretched by a force F. Let l be the elongation. Then stretching force increases uniformly from 0 to F. Therefore the average force

Displacement of free end = l
∴ Workdone in stretching = F_av × l
= \(\frac{1}{2}\)Fl = \(\frac{1}{2}\) × Force × extension
This work is stored as the elastic potential energy of the wire
ie. U = \(\frac{1}{2}\) × Fl
Volume of wire =AL
Workdorie in stretching per unit volume, U = \(\frac{\frac{1}{2} F \ell}{A L}\)

Stress = Y × strain ______(3)
Sub(3) in (2)
U = 1/2 × Y × strain × strain
U = 1/2 × Y × (strain)².

Applications Of Elastic Behavior Of Materials

1. Metallic ropes are used in the cranes for lifting the load because of its high elasticity.
2. While designing bridges and buildings, beams and columns are widely used. Bending of beams and columns under a load depends upon the Young’s modulus of the material used. To reduce the bending of a beam for a given load, material with larger youngs modulus is to be used.
3. The maximum height of the mountain is limited by the elastic properties of the rock which hold the mountain.

Question 2.
Find the radius of the rope that used to lift 10 tons(10000Kg). Elastic limit (maximum stress) of steel is 30 × 10⁷ N/m²
Answer:
The condition to withstand a force of 100 metric ton,

Question 3.
What is meant by buckling?

Answer:
If the load is not properly placed on a beam, the beam will bend side wise as shown in figure. This bending is called buckling.

Question 4.
Why the beams used in construction of bridges have a cross-section of the type I?
Answer:
Consider a solid rectangular beam of length l, breadth b and thickness d. If we place a load Mg at its centre, there will be a depression at the centre.

To reduce the depression at the centre, we have to increase d. But when d is large the beam will buckle unless the load is at the centre. This buckling can be avoided if the beam is given the section of the letter I. Such a beam is called I form girder.
It has following advantages

• It reduces the weight of the beam
• It saves material
• It prevents buckling

Question 5.
Find the height of mountain from the data given below. Maximum shearing stress = 30 × 10⁷ N/m² Density of material of mountain = 3 × 10³ Kgm^-3
Answer:
The force per unit area due to the weight of the mountain (at a depth h) is hrg. The material at the bottom experiences this force. The sides of the mountain are free. Hence the shear component is (hrg) itself.
∴ Shearing stress = hrg
30 × 10⁷ = h × 3 × 10³ × 10
h = 10 km
which is more than the height of Mount Everest.

Students can Download Chapter 8 Sources of Business Finance Notes, Plus One Business Studies Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Business Studies Notes Chapter 8 Sources of Business Finance

Contents

• Meaning, Nature and Significance of Business finance
• Equity shares – Features -Merits – Demerits
• Preference shares – Features – Types – Merits – Demerits
• Retained earnings – Features – Merits – Demerits
• Debentures – Features – Types – Merits – Demerits
• Public deposits – Features – Merits – Demerits
• Commercial Banks – Features – Merits – Demerits
• Financial institutions – Features – Merits – Demerits
• Trade credit – Features – Merits – Demerits
• Factoring – Features – Merits – Demerits
• Lease financing – Features – Merits – Demerits
• Commercial paper – Features – Merits – Demerits
• International financing – ADR – GDR – FCCB
• Factors affecting the choice of the source of fund Finance is the life blood of any business. The requirements of funds by business to carry out its various activities are called business finance.

Nature of Business Finance:
1. Fixed capital requirements:
In order to start a business funds are needed to purchase fixed assets like land and building, plant and machinery. This is called fixed capital requirement.

2. Working Capital requirements:
A business needs funds for its day to day operation. This is known as working Capital requirements. Working capital is required for purchase of raw materials, to pay salaries, wages, rent and taxes.

Classification of Sources of Funds:

1. Period Basis:
On the basis of period, the different sources of funds cari divided into 3. They are long-term sources, medium-term sources and short-term sources.
(a) Long Term Sources:
The amount of funds required by a business for more than five years is called long-term finance. Generally this type
of finance is required for the purchase of fixed assets like land and building, plant and machinery furniture etc. It include sources such as shares and debentures, long-term borrowings and loans from financial institutions.

(b) Medium Term Sources:
Where the funds are required for a period of more than one year but less than five years, is called medium-term sources. These sources include borrowings from commercial banks, public deposits, lease Financing and loans from financial institutions. This type of finance is required for modernization, renovation, special promotional programmes etc.

(c) Short Term Sources:
Short-term funds are those which are required for a period not exceeding one year. These sources include Trade credit, loans from commercial banks and commercial papers, etc. Short-term finance is used for financing of current assets such as accounts receivable and inventories.

2. Ownership Basis:
On the basis of ownership, the sources can be classified into ‘owner’s funds’and ‘borrowed funds’.
(a) Owners Fund:
It represent the amount of capital provided by owners and the amount of profit retained in the business. It is a permanent source of capital. Equity shares and retained earnings are the two important sources of ownership capital.

(b) Borrowed Funds:
It refers to funds mobilized from outsiders. It include loans from commercial banks, loans from financial institutions, issue of debentures, public deposits and trade credit.

Such sources provide funds for a specified period, on certain terms and conditions and have to be repaid with interest after the expiry of that period. Borrowed funds are provided on the security of some fixed assets.

3. Source of generation:
Another basis of categorising the sources of funds can be whether the funds are generated from within the organisation or from external sources.
(a) Internal sources:
Internal sources of funds are those that are generated from within the business. eg: ploughing back of profit, disposing of surplus stock etc.

(b) External sources:
External sources of funds are those that are generated from outside the business. eg: issue of debentures, borrowing from commercial banks and financial institutions and accepting public deposits.

SOURCES OF FINANCE:

• Issue of shares- (Equity and Preference Shares)
• Ploughing Back of Profit
• Issue of debentures
• Loan from Commercial bank
• Loan from Financial institutions
• Public deposits
• Lease Financing
• Long Term and Medium Term Sources of Finance
• Short Term Sources of Finance International Sources of Finance.

A business can raise funds from various sources. They are:

Issue of shares:
The capital of a company is divided into smaller units called share. Those who subscribe the shares of a company are known as ‘shareholders’. Two types shares may be issued by a company to raise capital. They are:

1. Equity Shares
2. Preference Shares

1. Equity Shares:
Equity shares represents the ownership capital of a company. They do not enjoy any preferential right in the matter of claim of dividend or repayment of capital. Equity share holders do not get a fixed dividend but are paid on the basis of earnings by the company. They bear the maximum risk. Equity shareholders are the owners of the company. They have right to vote and participate in the management.
Merits:

• Equity shares are suitable for investors who are willing to assume risk for higher returns
• Payment of equity dividend is not compulsory.
• Equity capital serves as permanent capital as it is to be repaid only at the time of liquidation of a company.
• Equity shares do not carry any charge on the assets of the company.
• They have right to vote and participate in the management.
• Equity capital provides credit worthiness to the company

Limitations:

1. Investors who want steady income may not prefer equity shares.
2. The cost of equity shares is generally more as compared to the cost of raising funds through other sources.
3. Issue of additional equity shares dilutes the voting power, and earnings of existing equity shareholders.
4. Issue of Equity shares is time consuming.

2. Preference Share:
The capital raised by issue of preference shares is called preference share capital. The preference shareholders enjoy a preferential right over equity shareholders in two ways:

• The right to get a fixed rate of dividend.
• The right to claim repayment of capital in the event of winding up of the company.

Preference shareholders generally do not enjoy any voting rights. A company can issue different types of preference shares.

Types of Preference Shares:
1. Cumulative and Non-cumulative Preference Share:
in cumulative preference shares, the unpaid dividends are accumulated and carried forward for payment in future years. On the other hand, in non- cumulative preference share, the dividend is not accumulated if it is not paid out of the current year’s profit.

2. Participating and Non-participating Preference Share:
Participating preference shares have a right to share the profit after making payment to the equity shares. The non-participating preference shares do not enjoy such a right.

3. Convertible and Non-convertible Preference Share:
The preference shares which can be converted into equity shares after a specified period of time are known as convertible preference share. Non-convertible shares cannot be converted into equity shares.

4. Redeemable and Irredeemable Preference Share:
Redeemable preference shares are those where the company undertakes to repay it after a specified period. Where the amount of the preference shares is refunded only at the time of liquidation, are known an irredeemable preference shares.
Merits:

1. Preference shares provide reasonably steady income in the form of fixed rate of return and safety of investment.
2. Preference shares are useful for those investors who want fixed rate of return with comparatively low risk
3. It does not affect the control of equity share holders because they have no voting right.
4. Preference shares do not create arty charge on the assets of the company.
5. They have a preferential right of repayment of capital over equity shareholders in the event of liquidation of a company.

Limitations:

1. Preference shareholders have no voting right.
2. The dividend paid is not deductible from profit for income tax.
3. These shares may not attract investors who are expecting higher returns.
4. The rate of dividend on preference shares is generally higher than the rate of interest on debentures.

Differences between Equity shares and Preference shares:

Retained Earnings (Ploughing Back of Profit):
A company generally does not distribute all its earnings amongst the shareholders as dividends. A portion of the net earnings may be retained in the business for use in the future. This is known as retained earnings. It is a source of internal financing or self financing or ‘ploughing back of profits’.
Merits:

1. It is a permanent source of funds available to an organization
2. No costs in the form of interest, dividend or flotation cost.
3. It is more dependable than external sources.
4. There is no commitment to pay dividend.
5. It increases the financial strength and earning capacity of the business.
6. Control over the management of the company remains unaffected.
7. It does not require the security of assets.
8. It may lead to increase in the market price of the equity shares of a company

Limitations:

1. Retained profits cause dissatisfaction among the shareholder because they get low dividend.
2. It attract competition in the market
3. It may attract government regulations.
4. It leads the management to manipulate the value of shares
5. It is uncertain source of fund because it is available only when profits are high.

Debentures:
A debenture is a document issued by a company under its seal to acknowledge its debt. Debenture holders are, therefore, termed as creditors of the corrfpany. Debenture holders are paid a fixed rate of interest.
Types of Debentures:
1. Secured and Unsecured Debentures:
Secured (Mortgaged) debentures are debentures which are secured by a charge on the assets of the company. Unsecured (Simple or naked) debentures do not carry any charge or security on the assets of the company.

2. Registered and Bearer Debentures:
In the case registered debentures, the name, address and other details of the debenture holders are entitled in the books of the company. The debentures which are transferable by mere delivery are called bearer (Unsecured) debentures.

3. Convertible and Non-convertible Debentures:
Convertible debentures are those debentures that can be converted into equity shares afterthe expiry of a specified period. On the other hand, nonconvertible debentures are those which cannot be converted into equity shares.

4. First and Second:
Debentures that are repaid before other debentures are repaid are known as first debentures. The second debentures are those which are paid afterthe first debentures have been paid back.
Merits:

1. It. is preferred by investors who want fixed income at lesser risk
2. Debenture holder do not have voting right
3. Interest on Debentures is a tax deductable expense
4. It does not dilute control of equity shareholders on management
5. Debentures are less costly as compared to cost of preference shares.
6. They guarantee a fixed rate of interest
7. It enables the company to take the advantage of trading on equity.
8. The issue of debentures is suitable when the sales and earnings are relatively stable

Limitations:

1. It is not suitable for companies with unstable future earnings.
2. The company has to mortgage its assets to issue debentures.
3. Debenture holders do not enjoy any voting rights.
4. In case of redeemable debentures, the company has to make provisions for repayment on the specified date, even during periods of financial difficulty.
5. With the new issue of debentures, the company’s capability to further borrow funds reduces.

Differences between Shares and Debentures:

Public Deposits:
The deposits that are raised by organisations directly from the public are known as public deposits. Rates of interest offered on public deposits are usually higher than those allowed by commercial banks.

Companies generally invite public deposits for a period up to three years. This is regulated by the R.B.I. and can not exceed 25% of its paid up share capital and reserves.
Merits:

1. The procedure for obtaining public deposits is simpler than share and Debenture.
2. Cost of public deposits is generally lower than the cost of borrowings from banks
3. Public deposits do not usually create any charge on the assets of the company
4. They do not have voting right therefore the control of the company is not diluted
5. Interest paid on public deposits is tax deductable.

Limitations:

1. New companies generally find it difficult to raise funds through public deposits
2. They are not secured.
3. They are costly as most Of the companies have to offer high interest.
4. It is an unreliable source of finance as the public may not respond when the company needs money

Commercial Banks:
Commercial Banks give loan and advances to business in the form of cash credit, overdraft, term loans, discounting of bills, letter of credit etc. Rate of interest on loan is fixed.
Merits:

1. Commercial Bank provide timely financial assistance to business.
2. Secrecy is maintained about loan taken from a Commercial Banks.
3. This is the easier source of finance as there is no need to issue prospectus and underwriting for raising funds.
4. Loan from a bank is a flexible source of finance.

Limitations:

1. Funds are generally available for short periods
2. Banks may ask for security of assets and personal sureties for sanctioning loan.
3. In some cases, difficult terms and conditions are imposed by banks for the grant of loan

Financial Institutions:
The state and central government have established many financial institutions to provide finance to companies. These institutions aim at promoting the industrial development of a country, these are also called ‘development Bank’.

These are IFCI, ICICI, IDBI and LIC, UTI. This source of financing is considered suitable when large funds for longer duration are required for expansion, reorganisation and modernisation of an enterprise.
Merits:

1. Financial Institution provide long term finance which is not provided by Commercial Bank
2. These institutions provide financial, managerial and technical advice and consultancy to business firms.
3. It increases the goodwill of the borrowing company in the capital market.
4. As repayment of loan can be made in easy installments, it does not prove to be much of a burden on the business.
5. The funds are made available even during periods of depression, when other sources of finance are not available.

Limitations:

1. The procedure for granting loan is time consuming due to rigid criteria and many formalities.
2. Financial Institution place restrictions on the powers of the borrowing company.
3. Financial institutions may have their nominees on the Board of Directors of the borrowing company thereby restricting the autonomy of the company.

Trade Credit:
Trade credit is a short term source of financing. The credit extended by one trader to another for purchasing goods or services is known as trade credit. The terms of trade credit vary from one industry to another and are specified on the invoice. Trade credit facilitates the traders to purchase goods without irpmediate payment.
Merits:

1. Trade credit is a convenient and continuous source of funds
2. It does not create any charge on the assets of the firm.
3. Trade credit may be readily available in case the credit worthiness of the customers is known to the seller
4. Trade credit needs to promote the sales of an organisation.

Limitations:

1. It may induce a firm to indulge in overtrading.
2. Only limited amount of funds can be generated through trade credit;
3. It is generally a costly source of funds as compared to other sources of fund.

Factoring:
Factoring is a method of raising short-term finance for the business in which the business can take advance money from the bank against the amount to be realised from the debtors. By this method, the firm shifts the responsibility of collecting the outstanding amount from the debtors on payment of a specified charge.

There are two methods of factoring-recourse and non-recourse. Under recourse factoring, the client is not protected against the risk of bad debts. Under non recourse factoring, full amount of invoice is paid to the client in the event of the debt becoming bad.
Merits:

1. Obtaining funds through factoring is cheaper than bank credit
2. Factoring provides steady cash inflow so that the company is able to meet its liabilities promptly.
3. It is flexible and ensures cash inflows from credit sales.
4. It does not create any charge on the assets of the firm;
5. The company can concentrate on important areas of business as the responsibility of credit control is shouldered by the factor.
6. Factors may give useful information about the credit standing of customers.

Limitations:

1. This source is expensive
2. The advance finance provided by the factor firm is generally available at a higher interest cost.
3. The factor is a third party to the customer who may not feel comfortable while dealing with it.

Lease Financing:
A lease is a contractual agreement whereby the owner of an asset (lessor) grants the right to use the asset to the other party (lessee). The lessor charges a periodic payment for renting of an asset for some specified period called lease rent.
Merits:

1. It enables the lessee to acquire the asset with a lower investment;
2. Lease rentals paid by the lessee are deductible for computing taxable profits;
3. It provides finance without diluting the ownership or control of business
4. The lease agreement does not affect the debt raising capacity of an enterprise;
5. Simple documentation makes it easierto finance assets.

Limitations:

1. A lease arrangement may impose certain restrictions on the use of assets.
2. The normal business operations may be affected in case the lease is not renewed.
3. The lessee never becomes the owner of the asset.

Commercial Paper(CP):
It is an unsecured promissory note issued by a firm to raise funds for a short period. The maturity period of commercial paper usually ranges from 90 days to 364 days. Being unsecured, only firms having good credit rating can issue the CP and its regulation comes under the purview of the Reserve Bank of India.
Merits:

1. A commercial paper does not contain any restrictive conditions;
2. As it is a freely transferable instrument, it has high liquidity;
3. A commercial paper provides a continuous source of funds.
4. They are cheaper than a bank loan.

Limitations:

1. Only financially sound and highly rated firms can raise money through commercial papers
2. The size of money that can be raised through commercial paper is limited
3. Commercial paper is an impersonal method of financing. Extending the maturity of a CP is not possible.
4. Issue of commercial paper is very closely regulated by the RBI guidelines.

International Financing:
1. Commercial Banks:
Commercial banks all over the world extend foreign currency loans for business purposes. Standard chartered is a major source of foreign currency loan to the Indian industry.

2. International Agencies and Development Banks:
A number of international agencies and development banks provide long and medium term loans and grants to promote the development of economically backward areas in the world. Eg. International Finance Corporation (IFC), EXIM Bank and Asian Development Bank.

3. International Capital Markets:
(a) Global Depository Receipts (GDR’s):
Uhder GDR, shares of the company are first converted into depository receipts by international banks. These depository receipts are denominated in US dollars. Then these depository receipts are offered for sale globally through foreign stock exchanges.

GDR is a negotiable instrument and can be traded freely like any other security. The holder of GDRs are entitled for dividend just like shareholders. But they do not enjoy the voting rights. Many Indian companies like ICICI, Wipro etc. have raised foreign capital through issue of GDRs.
Feature of GDR:

1. GDR can be listed and traded on a stock exchange of any foreign country other than America.
2. It is negotiable instrument.
3. A holder of GDR can convert it into the shares.
4. Holder gets dividends
5. Holder does not have voting rights.
6. Many Indian companies such as Reliance, Wipro and ICICI have issue GDR.

(b) American Depository Receipts (ADR’s):
The depository receipts issued by a company in the USA are known as American Depository Receipts.
Feature of ADR:

1. It can be issued only to American Citizens.
2. It can be listed and traded is American stock exchange.
3. Indian companies such as Infosys, Reliance issued ADR

Differences between ADR and GDR:

Foreign Currency Convertible Bonds (FCCB’s):
Foreign currency convertible bonds are equity linked debt securities that are to be converted into equity or depository receipts after a specific period.

The FCCB’s are issued in a foreign currency and carry a fixed interest rate. These are listed and traded in foreign stock exchange and similar to the debenture.
Factors affecting the choice of the source of funds:
The factors that affect the choice of source of finance are
1. Cost:
The cost of procurement of funds and cost of utilising the funds should be taken into account while deciding about the source of funds that will be used by an organization.

2. Financial strength and stability of operations:
In the choice of source of funds, business should be in a sound financial position so as to be able to repay the principal amount and interest on the borrowed amount. When the earnings of the organisation are not stable, it can issue equity shares to collect the fund.

3. Form of organisation and legal status:
The form of business organisation and status influences the choice of a source for raising money.

4. Purpose and time period:
Business should plan according to the time period for which the funds are required. A short-term need can be met through borrowing funds at low rate of interest through trade credit, commercial paper, etc. For long term finance, sources such as issue of shares and debentures are more appropriate.

5. Risk profile:
Business should evaluate each of the source of finance in terms of the risk involved.

6. Control:
business firm should choose a source keeping in mind the extent to which they are willing to share their control over business.

7. Effect on credit worthiness:
The dependence of business on certain sources may affect its credit worthiness in the market.

8. Flexibility and ease:
Another aspect affecting the choice of a source of finance is the flexibility and ease of obtaining funds.

9. Tax benefits:
Various sources may also be weighed in terms of theirtax benefits. For example, while the dividend on preference shares is not tax deductible, interest paid on debentures and loan is tax deductible.

Students can Download Chapter 8 Gravitation Notes, Plus One Physics Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Physics Notes Chapter 8 Gravitation

Summary
Introduction
Gravitational force is one of the fundamental forces exist in nature. All celestial bodies in the universe are moving under the influence of the gravitational force.

Kepler’S Laws
The three laws of Kepler are Known as

1. Law of orbits
2. Law of areas
3. Law of periods

1. Law of Orbits: All planets move in elliptical orbits with the sun situated at one of the foci of the ellipse.
Ellipse:
An ellipse is the path traced out by a planet around the sun. The closest point ‘P’ is called the perihelion and Athe aphelion. The semimajor axis is half the distance AP.

Drawing an ellipse:

Select two points F₁ and F₂. Take a length of a string and fix its ends at F₁ and F₂ by pins. With the tip of a pencil stretch the string and then draw a closed curve. F₁ and F₂ are called the focii.

2. Law of areas: The line that joins any planet to the sun sweeps equal areas in equal intervals of time, ie. aerial velocity is constant
Proof:

Let the sun be at the origin and let the position and momentum of the planet be denoted by \(\overrightarrow{\mathrm{r}}\) and \(\overrightarrow{\mathrm{p}}\). Let ∆\(\overrightarrow{\mathrm{A}}\) be the area swept out by the planet of mass m in time interval A t.
From the figure:

But we know angular momentum of a planet is constant because the gravitational force is central force. Hence we get \(\frac{\Delta \overline{\mathrm{A}}}{\Delta \mathrm{t}}\) = a constant.
Note:

1. Gravitational force is a central force. If direction of force on the planet is along the vector joining sun and planet, it is called central force.
2. The law of area is the consequence of conservation of angular momentum.

3. Law of periods (Kepler’s third law): The square of the time period of revolution of a planet is proportional to the cube of the semi major axis of the ellipse traced out by the planet.
T² α a³
Where ‘a’ is semi major axis.

Universal Law Of Gravitation
On the basis of Keplers laws and observations of motion of planets, Newton gave a universal law of force acting between any two particles of matter.

Statement:
Every body in the universe attracts each other with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
Explanation

Consider two masses m₁ and m₂ separated by a distance r. The force of attraction between two particles can be written as

The above equation can be written in vector form as

\(\hat{\mathbf{r}}\) is the unit vector from m₁ to m₂. G is a constant called the gravitational constant. In S.l. Unit G = 6.67 × 10^-11 Nm² × \(\bar{g}^{2}\).
Note:

1. The negative sign of gravitational force shows it is an attractive force.
2. \(\vec{F}_{12}=-\vec{F}_{21}\) ie; force on I^st particle due to II^nd particle = – force on II^nd particle due to I^st particle.

Deduction of Kepler’s third law:
Planet of mass m is orbiting around the sun of mass M in circular orbit of radius r, with constant angular velocity w, then.
Centripetal force = Gravitational force.

The above result holds equally good for elliptical orbit provided we replace r with a. (the semi major axis of the elli pse)

The Gravitational Constant
The value of the gravitational constant G can be determined experimentally. This was first done by English scientist Henry Cavendish in 1798.
Cavendish experiment to determine gravitational constant:

Two equal masses (m) are attached at two ends of the rod of length L. The bar is suspended from a rigid support by a fine wire. When two large lead spheres are brought close to small ones from opposite sides as shown, a deflecting torque is produced.
deflecting torque τ = F × L
= \(\frac{G M m}{d^{2}}\) × L
Where d is the distance between m and M. Due to this deflecting torque a restoring couple is produced on the wire.
For equilibrium,
Deflecting couple = Restoring couple

Where ‘C’ is the restoring couple per unit twist and θ is the angle of rotation. Knowing C, θ, d, M, m and L, we can calculate G. The currently accepted
value is G = 6.67 × 10^-11 Nm²/kg²

Question 1.
is it possible to shield a body from gravitational effect?
Answer:
It is not possible to shield a body from gravitational effect because the gravitational force does not depend on the nature of the intervening medium.

Acceleration Due To Gravity Of The Earth
Acceleration due to gravity is the acceleration experienced by a body falling freely towards the earth.
Relation between acceleration due to gravity and gravitational constant:
Consider a body of mass ‘m’ at a distance ‘r’ from centre of earth. According to Newton law of
Gravitation, F = \(\frac{\mathrm{GMm}}{\mathrm{r}^{2}}\) ______(1)
Force acting on mass ‘m’
F = mg ______(2)
comparing eq(1) and eq(2)
g = \(\frac{G M}{r^{2}}\)
On the surface of earth r = R.
∴ acceleration due to gravity on the surface of earth

The value of g is 9.8 m/s². There is a slight variation for g from place to place depending on the height or depth of the place.

Question 2.
Where is the maximum value of g on the surface of earth. Why?
Answer:
It is on the poles. The distance between the pole and centre of earth is minimum at the poles. Hence
g = \(\frac{G M}{R^{2}}\) is maximum at the poles.

Question 3.
There is a popular statement regarding Convendish: “Cavendish weighed the earth”. Comment on this statement.
Answer:
Acceleration due to gravity g = \(\frac{G M}{R^{2}}\)
∴ M = \(\frac{\mathrm{gR}^{2}}{\mathrm{G}}\)
Knowing g, R, and G, we can find the mass of earth. The value of G is experimentally found out by Covendish. This is the reason for the above statement.

Acceleration Due To Gravity Below And Above The Surface Of Earth
1. Variation of ‘g’ with altitude:
The acceleration due to gravity on the surface of earth,
g = \(\frac{G M}{R^{2}}\) _____(1)

At a height h, the acceleration due to gravity can be written as,
g_h = \(\frac{\mathrm{Gm}}{(\mathrm{R}+\mathrm{h})^{2}}\) _____(2)
eq(1)/eq(2)

This equation shows that acceleration due to gravity decreases as height increases. The above equation is valid when h<<R.

2. Variation of g with depth:

If we assume the earth as a sphere of radius R with uniform density r,
mass of earth = volume × density
M = \(\frac{4}{3}\) πR³ ρ _____(1)
We know acceleration due to gravity on the surface, GM
g = \(\frac{G M}{R^{2}}\) ______(2)
Substituting eq(1) in eq(2), we get

g = \(\frac{4}{3}\) πGR_ρ ______(3)
Therefore the acceleration due to gravity at a depth d is given by
g_d = \(\frac{4}{3}\) πG(R – d)ρ _______(4)
eq(4)/eq(3)

The above equatiqn shows that, when depth increases g decreases.

Gravitational Potential Energy
Gravitational potential energy:
The gravitational potential energy of a body at a point is defined as the amount of workdone in bringing the body from infinity to that point without acceleration.
Expression for gravitational P.E:

Consider the earth as a uniform sphere of radius R and mass M. Consider a point A at distance ‘r’ from the centre of earth. P is another point at a distance ‘x’ from O. Q lies at distance dx from P.

By definition, the gravitational potential energy of the body at point A, is the work done in bringing the body of mass ‘m’ from infinity to that point A. The gravitational force on the body at the point P is given by F = \(\frac{\mathrm{GMm}}{\mathrm{x}^{2}}\).
If the body is displaced from P to Q Work done,
dw = F.dx
= \(\frac{\mathrm{GMm}}{\mathrm{x}^{2}}\). Therefore, workdone in bringing the body from infinity to the point A,

Since this workdone is stored inside the body as its gravitational potential energy, the gravitational potential energy (U) of a body of mass m at distance r from the centre of the earth is given by,

Question 4.
Gravitational potential energy at a point, U = \(\frac{-\mathrm{GMm}}{\mathrm{r}}\)

1. What is meant by negative sign in the above equation.
2. What is the value of U at r = ∞

Answer:

1. Negative sign shows that the potential energy is due to attractive gravitational force. It means, to bring a body from infinity to point P, work has been done by the gravitational field of earth, ie; by attractive force.
2. When r = ∞, the gravitational potential energy becomes zero.

Note: Maximum value of gravitational potential energy is zero.
Gravitational Potential:
The gravitational potential at a point is the amount of workdone in bringing a unit mass from infinity to that point without acceleration.
Explanation
Gravitational potential energy of mass m at a point is v = \(\frac{-\mathrm{GMm}}{\mathrm{r}}\)
If we take, m = 1 we get gravitational potential.
∴ Gravitational potential v = \(\frac{-G M}{r}\)
Note: The gravitational potential at infinity is taken to be zero.

Question 5.
What is the difference between gravitational potential energy and gravitational potential?
Answer:
Gravitational potential energy of mass m at a distance ‘r’ from centre of earth.
w = \(\frac{-\mathrm{GMm}}{\mathrm{r}}\)
But gravitational potential at a distance r from the centre of earth, w = \(\frac{-G M}{r}\)
From the equation we can understand that, gravitational potential energy depends on the mass of the body. But gravitational potential at point is independent of the mass of the body.

ESCAPE SPEED
The minimum speed with which a body is projected so that it never returns to the earth is called escape
speed or escape velocity.
Expression for escape speed:
Force on a mass m at a distance r from the centre of earth = \(\frac{\mathrm{GMm}}{\mathrm{r}^{2}}\)
Work done for giving small displacement dr,

Work done in taking the body to infinity from surface of earth,

This energy is given in the form of K.E. = \(\frac{1}{2}\)mv²_e
where v_e is the escape speed

This escape velocity \(\sqrt{2 \mathrm{Rg}}\) estimated to be 11.2 km/s on the earth. But escape velocity of moon is 2.3 km/s.
Note: Escape velocity is independent of mass of the escaping body.

Question 6.
Moon has no atmosphere. Why?
Answer:
Escape velocity on moon is 2.3 km/s. The r.m.s. velocity of the gas molecules is greater than this value. Gas molecules easily escape from the surface of moon. Hence there is no atmosphere on moon.

Earth Satellites
Satellites:
The moon is the natural satellite of the earth. It goes round the earth in about 27.3 days almost in a circular. Orbit of radius 3.84 × 10⁵ km. The gravitational force of attraction between the earth and the moon supplies the necessary centripetal force to keep the moon in its circular orbit.
Artificial Satellites:
A man made satellite is called an artificial satellite.
eg: INSAT, EDUSATetc.
Orbital velocity of a satellite:
Orbital velocity of a satellite is the velocity required for a satellite to revolve round the earth in a fixed orbit.
Expression for orbital velocity:
Consider a satellite of mass m revolving with orbital velocity ‘v’ around the earth at a height ‘h’ from the surface of earth. Let M be the mass of earth and R be radius of earth.

The gravitational force of attraction between earth and satellite.

Centripetal force required forthe satellite

For stable rotation,
Centripetal force = Gravitational force

The above equation shows that orbital velocity decreases as h increases.
Period of satellite:
Period of satellite is time taken by the satellite to revolve once around the planet in a fixed orbit.


Case -1
For a minimum orbit
For a satellite very close to the surface of earth, h can be neglected in comparison to R.
ie; R + h ≈ R

Where T₀ is called period of minimum orbit. If we substitute the value g = 9.8 m/s² and R = 6400 km,
We get

T₀ = 85 minutes.

Energy Of An Orbiting Satellite
The kinetic energy of the satellite in a circular orbit at height h from surface of earth with speed vis k.E
= \(\frac{1}{2}\) mv²

The potential energy at distance (R+h) from the centre of the earth is P.E = \(\frac{-G M m}{(R+h)}\)
∴ Total energy E = k.E. + p.E

Question 7.
What is the physical meaning of -ve energy?
Answer:
If total energy of satellite is negative, it moves in a closed path. This satellite can’t escape from earth’s gravitational field.

Question 8.
What is the condition fortotal energy to escape from earth’s gravitational field.
Answer:
If total energy of satellite is zero or positive, it can escapes to infinity.

Geostationary And Polar Satellites
A geostationary satellite is a satellite which appears to be stationary in the sky. The period of this satellite must be the same as the period of the rotation of the earth about its own axis. Its direction of rotation is from west to east.

Question 9.
Calculate the height of geostationary satellite.
Answer:
If h is the height of satellite, period

Substituting the value of
T = 24 × 60 × 60 sec., and
R= 6400 × 1000 m g = 9.8 m/s²
we get

R + h = 42648.54 km.
h = 42648.54 – R = 42648.54 – 6380
h = 36268.54 km.
Example: INSAT
Polar satellite:

Polar satellite orbits in the north-south direction. The height of polar satellite is 500 to 800 km. Since its time period is around 100 minutes, it crosses any altitude many times a day. The camera fixed on the satellite can view small strips of the earth in one orbit.

Adjacent strips are viewed in the next orbit. So that in effect the whole earth can be viewed strip by strip during the entire day. This type of satellite is used for remote sensing, meteorology and environmental studies.

Weightlessness
A satellite can be considered to be a continuously falling body. Since a freely falling body experiences weightlessness, the satellite and object inside it feel weightlessness.

Students can Download Chapter 7 Formation of a Company Notes, Plus One Business Studies Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Business Studies Notes Chapter 7 Formation of a Company

Contents

• Promotion- Functions and Legal position of promoter
• Incorporation-Steps
• Capital subscription-Steps
• Commencement of business- Steps
• Memorandum of Association and its clauses- Articles of Association and its clauses- Prospectus and its clauses
• Differences between Memorandum and Articles of Association

The steps involved in the formation of a company are:

• Promotion
• Incorporation
• Capital subscription
• Commencement of business

Promotion:
Promotion is the first stage in the formation of a company. The identification of business opportunities, analysis of its prospects and initiating steps to form a joint stock company is called promotion. The person who undertakes to form a company is called promoter.
Functions of a Promoter:
1. Identification of business opportunity:
The first and foremost activity of a promoter is to identify a business opportunity.

2. Feasibility studies:
After identifying a business opportunity, the promoters undertake some feasibility studies to determine the viability and profitability of the proposed activity.

• Technical feasibility: To determine whether the raw materials or technology is easily available
• Financial feasibility: To determine the total estimated cost of the project
• Economic feasibility: To determine the I profitability of the proposed project

3. Name approval:
After selecting the name of company the promoters submit an application to the Registrar of companies for its approval. The selected name is not the same or identical to an existing company.

4. Fixing up signatories to the Memorandum of Association:
Promoters have to decide about the members who will be signing the Memorandum of Association of the proposed company.

5. Appointment of professional:
Promoters appoint merchant bankers, auditors etc. to assist them in the preparation of necessary documents.

6. Preparation of necessary documents:
The promoters prepare certain legal documents which are to be submitted to the Registrar of companies. They are

• Memorandum of Association
• Articles of Association,
• Consent of proposed Directors
• Agreement, if any, with proposed managing or whole time director
• Statutory declaration

Position of Promoters
The promoter is neither an agent nor a trustee of the company. The promoter stands in the fiduciary relationship with the company. He should not make any secret profits out of the dealings. Any, such gains are to be disclosed.

The promoter must act honestly, in good faith and in the best interest of the company. The promoter is personally liable for all the preliminary contracts with the other parties before incorporation. The promoter is also liable for any omission of facts or false statements in the prospectus.

Incorporation:
A company comes into existence only when it is registered with the Registrar of Companies. For this purpose the promoter has to take the following steps.
Steps for Incorporation:
(a) Application for incorporation:
Promoters make an application for the incorporation of the company to the Registrar of companies.

(b) Filing of documents:
The following documents must be filed with the Registrar of Companies for incorporation.

1. The Memorandum of Association duly stamped, signed and witnessed
2. Articles of Association duly stamped, signed and witnessed
3. Written consent of the proposed directors
4. Agreement, if any, with proposed managing or whole time director
5. A copy of the Registrar’s letter approving the name of the company.
6. Statutory declaration
7. A notice about the exact address of the registered office.
8. Documentary evidence of payment of registration fees.

The Registrar verifies the entire document submitted. If he is satisfied then he enters the name of the company in his Register. After the registration, the Registrar issues a Certificate called Certificate of Incorporation.

This is called the birth certificate of the company. With effect from November 1, 2000, the Registrar of Companies allots a CIN (Corporate Identity Number) to the Company.

Effect of the Certificate of Incorporation Certificate of Incorporation is the conclusive evidence of the legal existence of the company. A private company can commence its business after receiving Certificate of Incorporation. The certificate of incorporation is the birth certificate of the company.

Capital Subscription:
A public company can raise funds from the public by issuing shares and Debentures. Forthis it has to issue prospectus. The following steps are required for raising funds from the public:

1. A.public company is required to take approval from SEBI. (Securities and Exchange Board of India)
2. File a copy of prospectus or a statement in lieu of prospectus with the Registrar of Companies.
3. Appointment of Bankers, Brokers, Underwriters:
4. Ensure that minimum subscription is received;
5. Application for listing of company’s securities;
6. Refund/adjust excess application money received;
7. Issue allotment letters to successful applicants;
8. File return of allotment with the Registrar of Companies (ROC).

Commencement of Business:
A public company can commence business only after getting certificate of commencement of business from the Registrar. The company must file the following documents to obtain the certificate of commencement of business.

1. Declaration that the minimum subscription has been received in cash to allot shares.
2. A declaration that all directors have taken up and paid for their qualification shares
3. A statutory declaration stating that necessary legal formalities have been complied with has to be filed.

The Registrar shall examine these documents. If these are found satisfactory, a ‘Certificate of Commencement of Business’ will be issued. This certificate is conclusive evidence that the company is entitled to do business.

With the grant of this certificate the formation of a public company is complete and the company can legally start doing business. Documents used in the formation of a company.

Memorandum of Association:
It is the charter or magnacarta of the company. It defines the objects of the company and provides the framework beyond which the company cannot operate. It lays down the relationship of the company with outside world.

Memorandum of Association must be printed, divided into paragraphs, numbered consecutively. The Memorandum of Association must be signed by at least seven persons in case of a public company and by two persons in case of a private company.

Contents of Memorandum of Association:

1. The name clause: Under this clause the name of the company is mentioned. A company can select any name subject to the following restrictions.

1. The proposed name should not be identical with the name of another company
2. A name which can mislead the public
3. In case of a public company the name should end with the word ‘Limited’ and in case of a private company the name should end with the word ‘Private Limited’
4. The name must not directly or indirectly imply any participation of the Central or State Govt.
5. The name must not suggest any connection or patronage of a national hero
6. It should not include the word co operative.

2. Registered office clause:
This clause contains the name of the state, in which the registered office of the company is proposed to be situated. It must be informed to the Registrar within thirty days of the incorporation of the company.

3. Objects clause:
This is the most important clause of the memorandum. It defines the purpose for which the company is formed. A company is not legally entitled to undertake an activity, which is beyond the objects stated in this clause.

4. Liability clause:
It states that the liability of members is limited to the face value of shares held by them or the amount guaranteed to be paid on winding up.

5. Capital clause:
This clause specifies the maximum capital which the company will be authorised to raise through, the issue of shares.

6. Association clause:
In this clause, the signatories to the Memorandum of Association state their intention to be associated with the company and also give their consent to purchase qualification shares.

Articles of Association:
The Articles of Association is the second important document of a company. The Articles define the rights, duties and powers of the officers and the Board of directors. It contains the rules regarding internal management of the company. It shows the relationship between the company and its members.
Contents of Articles of Association:

1. The share capital of the company and its division.
2. Rights of each class of shareholders.
3. Details of contracts made with different parties.
4. Procedure for making allotment of shares.
5. Procedure for issuing share certificate.
6. Procedure for transfer and transmission of shares.
7. Procedure for forfeiture and reissue of shares.
8. Procedure for conducting meetings, voting, proxy and poll
9. Procedure for appointing, removal and remuneration of directors.
10. Procedure for declaration of and payment of dividend.
11. Keeping books of account and audit of the company.
12. Procedure regarding alteration of share capital.
13. Procedure regarding winding up of the company.

Table A:
A public limited company may adopt Table A which is a model set of articles given in the Companies Act. Table A is a document containing rules and regulations for the internal management of a company. If a company adopts Table A, there is no need to prepare separate Articles of Association.

Difference between Memorandum of Association and Articles of Association:

Prospectus:
Prospectus is a document issued by the public companies inviting the public to subscribe for shares or debentures of the company. It contains all information regarding the company’s affairs and its future prospects.

A prospectus must be dated and signed by all the directors. A copy of the prospectus must be filed with Registrar before it is issued to public.
Contents of prospectus:

1. Name and address of the registered office of the company.
2. Main objects of the company.
3. Classes of shares and debentures.
4. Name, address and occupation of the signatories to the memorandum.
5. Details of the borrowing powers of the company.
6. Name, address and occupation of the directors and managing director.
7. Name and address of the promoters.
8. Minimum subscription.
9. Time of opening and closing of subscription.
10. The amount payable on application and allotment of each class of shares.
11. Name of underwriters.
12. Details of preliminary expenses.

Companies which do not want to issue a prospectus may submit a statement in lieu of prospectus to the Registrar of Companies. It is a copy of the prospectus but is not issued to the public.

Statement in lieu of prospectus:
Sometimes a company may not invite public subscription and hence may not issue a prospectus. In such a case the Companies Act provides that at least three days before the first allotment, a statement called Statement in lieu of prospectus must be filled with the Registrar for registration of a company. It is drafted according to the Part 1 of Schedule 3 of the Act.

Minimum Subscription:
Minimum subscription is the minimum amount of shares that must be subscribed by the public. A company can make allotment of shares only after receiving the minimum subscription. Otherwise, the application money received must be returned to the applicants. Minimum subscription is 90% of the total number of shares offered to the public.

Preliminary contract:
During the promotion of the company, promoters enter into certain contracts with third parties on behalf of the company. These are called preliminary contracts. Promoters are personally liable to third parties for these contracts.

Qualification Shares:
According to the Articles of Association, a director must take a certain number of shares in a company to act as a director. These are called Qualification Shares. They have to pay for these shares before the company obtains Certificate of Commencement of Business.

Underwriting:
The process of appointing underwriters to ensure the minimum subscription of capital is known as underwriting. Underwriters undertake to buy the shares if these are not subscribed by the public. For this, they get underwriting commission.

Students can Download Chapter 7 Systems of Particles and Rotational Motion Notes, Plus One Physics Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Physics Notes Chapter 7 Systems of Particles and Rotational Motion

Summary
Introduction
In the earlier chapters we discussed the motion of particle. We applied the results of our study to the motion of bodies of finite size.

A large class of problems with extended bodies can be solved by considering them to be rigid bodies. Ideally a rigid body is a body with a perfectly definite and unchanging shape. The distances between different pairs of particles of such a body do not change.

(i) Basically a rigid body can have two types of motion.

1. translational
2. Rotational motion

1. Translational motion:

In pure translational motion, at any instant of time every particle of the body has the same velocity. Explanation
Consider a rectangular block moving down along an inclined plane as shown in the figure: This body is rigid. Hence all the particles have same velocity. Any points like P1 or P2 of the body moves with the same velocity at any instant of time.

2. Rotational motion:
In pure rotational motion at any instant of time every particle of the body have different velocities. Explanation

Consider a cylinder rolling down along inclined plane as shown in figure. Points P1, P2, P3 and P4 have different velocities (shown by arrows) at any instant of time.
Note: The above figure shows a combination motion of both translational and rotational motion.

Centre Of Mass
The centre of mass of a system of particles is the point where all the mass of the system may be assumed to be concentrated.
Position vector of two particle system:

Consider two particles of masses m1 and m2 with position vectors \(\vec{r}_{1}\) and \(\vec{r}_{2}\) respectively with respect to the origin O. Now the position coordinate of the center of mass C is defined as.

X, Y and Z coordinate of centre of mass of two particle system

Position vector of N particle system:
Consider a system of N particles of mass m₁, m₂…….,mN with position vectors \(\vec{r}_{1}, \vec{r}_{2}, \ldots \ldots \ldots \vec{r}_{N}\) respectively. Then the centre of mass of the system of N particle is defined as

Position vector of CM of continuous distribution of mass:
If body is continuous distribution of mass, we divide the body into n small elements of mass: Dm₁, Dm₂,………..DmN. Let r₁, r₂,……….rN be the position vectors of those small elements respectively.
Then position vector of CM is,

when we take N as bigger ((Dmi) becomes smaller) the summation can be changed into integration.

Motion Of Centre Of Mass
Velocity of centre of mass. The position vector of the centre of mass of N particle system is given

Differentiating the position vector of C.M., we get velocity of CM. ie;

Acceleration of centre of mass:
Acceleration of centre of mass a = \(\frac{\mathrm{d}}{\mathrm{dt}} \overrightarrow{\mathrm{v}}\)

Force acting on the centre of mass:
Force acting on the centre of mass = Total mass at the centre of mass × acceleration of the centre of mass.
ie; \(\overrightarrow{\mathrm{F}}\) = M\(\overrightarrow{\mathrm{a}}\) ______(1)
But F = F_internal + F_extenal
By Newton’s third law, sum of the internal forces is zero.
∴ F = F_extenal
Therefore eq(1) becomes

Therefore the centre of mass moves as if it were a particle of mass equal to the total mass of the system and all the external forces are acting on it.

Linear Momentum Of A System Of Particles
Momentum of centre of mass
Velocity of centre of mass,

The equation means that, the total momentum of a system of particles is equal to the product of the total mass of the system and the velocity of its centre of mass.
Momentum conservation and centre of mass motion:
statement:
The total momentum of the centre of mass is conserved if no external force acts.
Proof:
According to Newton’s second law, rate of change momentum of centre of mass is directly proportional s to force acting on it.

If the total external force acting on the system is zero; the centre of mass moves with a constant velocity.
Application of the idea of centre of mass:

1. Explosion of a shell inflight

Consider a shell projected into air. If it is not exploded, its path will be a parabola. If it is exploded in air, the centre of mass follows the same parabolic path. Because the forces due to explosion are internal. Internal force can’t change the direction of centre of mass.
Note: External force can change the direction of centre of mass

2. Decay of radio active nuclei at rest:

Consider radioactive decay of radium nucleus moving along a straight line. A radium nucleus disintegrates into a nucleus of radon and an alpha particle. The two particles produced in the decay move in different directions. But the centre of mass (of radon and α particle) moves along a straight line, because the force leading to decay is internal. Internal force can’t change the direction of centre of mass.

Centre of mass frame:
If we observe this decay from the frame of reference in which the centre of mass (of a particle and radon) at rest, the product particle seems to be moving in opposite direction along a straight line.

In centre of mass frame, the motion of product particles become simple.

3. Binary stars:

Consider the trajectories of the two stars of equal mass as shown in figure. If there are no external forces, the centre of mass moves along a straight line as shown in figure.

Centre of mass frame of Binary stars:
If we look the trajectories of S₁ and S₂ from the centre of mass frame, we find that these two stars are moving in a circle as shown in figure.

In this frame of reference, the trajectories of the stars are a combination of

1. uniform motion in a straight line of the centre of mass and
2. circular orbits of the stars about the centre of mass.

Vector Product Of Two Vectors
The vector product of two vectors \(\overrightarrow{\mathrm{a}}\) and \(\overrightarrow{\mathrm{b}}\) is


Screw rule:
Rotate a right handed screw from \(\overrightarrow{\mathrm{a}}\) to \(\overrightarrow{\mathrm{b}}\). Then the direction of advance of the. tip of the screw gives the direction of (\(\overrightarrow{\mathrm{a}}\) × \(\overrightarrow{\mathrm{b}}\))

Right hand rule:
Curl the fingers of the right hand from \(\overrightarrow{\mathrm{a}}\) to \(\overrightarrow{\mathrm{b}}\) along the shorter angle. Then the direction in which the thumb points gives the direction of (\(\overrightarrow{\mathrm{a}}\) × \(\overrightarrow{\mathrm{b}}\)).

Properties of cross product:

Note:
If \(\hat{i}, \hat{j}, \hat{\mathbf{k}}\) occur cyclically in the above vector product relation, the vector product is positive. If \(\hat{i}, \hat{j}, \hat{\mathbf{k}}\) do not occur in cyclic order, the vector product is negative.

Question 1.

Answer:

Angular Velocity And Its Relation With Linear Velocity
In earlier chapter, we treated angular velocity as scalar. But angular velocity is a vector quantity. The relation between angular velocity and linear velocity can be written in vector notation as

Direction of angular velocity:

Consider a body moving along the circumference of circle of radius ‘r’with velocity v. Then the direction of angular velocity will be perpendicular to both \(\overrightarrow{\mathbf{V}}\) and \(\overrightarrow{\mathbf{r}}\) (along the axis of rotation).

The figure(1) shows the direction of w, if body rotates in clockwise direction.

The figure(2) shows the direction of w, if body rotates in anticlockwise direction.
1. Angular acceleration:
Rate of change of angular velocity is called angular acceleration.
angular acceleration \(\vec{\alpha}=\frac{\mathrm{d} \vec{\omega}}{\mathrm{dt}}\)
If the axis of rotation is fixed, the direction of ω and hence α is fixed. In this case the vector equation reduces to scalar equation.

Torque And Angular Momentum
Torque and angular momentum are important quantities to discuss the motion of rigid bodies.

1. Moment of force (Torque)
Torque (or the moment) of a force of about a point is the rotating effect of the force about that point.
Explanation

If f is the force acting at a point A, then torque about a point O is given by


Where \(\overrightarrow{\mathbf{r}}\) is the position vector of the point A from the point O. Torque is a vector quantity. The direction of torque is (given by right hand screw rule). Perpendicular to both \(\overrightarrow{\mathbf{r}}\) and \(\overrightarrow{\mathbf{f}}\).
Unit:
The unit of torque is Nm.
Note:

• If the turning tendency of the force is anticlockwise, then the torque is positive and if it is clockwise, then torque is negative.
• Torque has dimensions ML²T^-2. Its dimensions are the same as those of work or energy. Torque is. vector, while work is scalar.
• Torque plays the same role in rotational motion as force does in translational motion.

Couple:
Two equal and opposite forces, separated by a distance, constitute a couple.

Moment of couple (Torque):
The moment of couple is the product of either of the forces and the perpendicular distance between them.

Question 2.
The door is a rigid body which can rotate about a fixed axis passing through the hinges. What makes the door rotate?
Answer:
A force applied to the hinge line can’t produce any rotation. But a force of given magnitude applied at right angles to the door at its outer edge is most effective in producing motion. The rotational analogue of force is moment of force. It is also referred to as torque.

Question 3.
When you fix a handle on a door where do you fix it?
Answer:
You fix it in such a way that the torque is maximum. For this the lever arm must be maximum. So the handle is fixed as far away from the hinges as possible Note: A couple produces rotation without translation motion.

2. Angular momentum of a particle:
Angular momentum of a particle about a point is defined as the moment of its linear momentum about that point.
Explanation

Considers particle of mass ‘m’ and linear momentum \(\overrightarrow{\mathbf{p}}\) at a position \(\overrightarrow{\mathbf{r}}\) relative to the origin O. The angular momentum \(\overrightarrow{\mathbf{l}}\) of the particle can be written as (with respect to the origin O).

Note:

• The quantity angular momentum is the rotational analogue of linear momentum.
• Direction of \(\overrightarrow{\mathbf{l}}\) is given by right hand screw rule, (angular momentum is perpendicular to both \(\overrightarrow{\mathbf{r}}\) and \(\overrightarrow{\mathbf{p}}\)).

Relation between angular momentum and torque:
Angular momentum of a particle,

When differentiate on both side, we get


ie The rate of change of angular momentum is the torque applied to it. This is similar to force equal to rate of change of linear momentum.

Torque and angular momentum for a system of particles:
Consider a system having n particles. The total angular momentum of system is the vector sum of angular momentum of individual particles.
∴ total angular momentum of system,

\(\frac{\mathrm{dL}}{\mathrm{dt}}=\tau\) _____(1)
But Στ_i = τ is the total torque acting on the system of particle. Actually torque acting on a system is sum of external torque (τ_ext) and internal torque (τ_int)
ie. τ = τ_ext + τ_int
But τ_int = 0, because internal torque arises due to action – reaction pair. Action reaction pair for a system is zero.
∴ τ = τ_ext ______(2)
substituting eq(2) is eq (1) we get
\(\frac{\mathrm{d} \overrightarrow{\mathrm{L}}}{\mathrm{dt}}=\tau_{\mathrm{ext}}\)
The above equation means that, the time rate of the total angular momentum of a system of particles about a point is equal to the sum of the external torques acting on the system taken about the same point.

Conservation of angular momentum of a system:
For a system of particles,


If the total external torque on a system of particles is zero, then the total angular momentum of the system is conserved.
Note: The statement that the total angular momentum is conserved means that each of these three components (Lx, Ly, Lz) is conserved.

Equilibrium Of A Rigid Body
A rigid body is said to be in a mechanical equilibrium, if both it’s linear momentum and angular momentum are not changing with time.

(or)

A body is said to be in mechanical equilibrium, if the body has neither linear acceleration nor angular acceleration. A body moving with constant momentum is said to . be in translational equilibrium. Similarly a body with constant angular momentum is said to be in rotational equilibrium.

Condition for translational equilibrium:
If the total force acting on a rigid body is zero, the body, moves with constant linear momentum (or zero linear acceleration). The body moving with constant linear momentum is said to be in translational equilibrium Undertranslational equilibrium, the total force acting on the rigid body is zero.

Condition for rotational equilibrium:
If the total torque acting on rigid body is zero, the total angular momentum of the body does not change. Then the body is said to be in rotational equilibrium. Mathematical condition for rotational equilibrium is

Principles of moments:

Consider a lever pivoted at some origin (say fulcrum) in mechanical equilibrium. Let \(\overrightarrow{\mathrm{f}}_{1}\) and \(\overrightarrow{\mathrm{f}}_{2}\) he the forces acting at A and B as shown in figure. Let \(\overrightarrow{\mathrm{R}}\) be the reaction of the support at the fulcrum. For translational equilibrium

For rotational equilibrium, sum of moments must be zero.
ie d₁f₁ + -d₂f₂ = 0
d₁f₁ = d₂f2₂ ______(2)
In the case of lever, f₁ is used to lift some weight. Hence f₁ is called load and its distance from the fulcrum d₁ is called load arm. Force f₂ is the effort applied to lift the load, distance d₂ is called effort arm.
Hence d₁f₁ = d₂f₂ can be written as
load arnn × load = effort arm × effort
The above equation expresses the principle of moments for a lever.
The ratio \(\frac{f_{1}}{f_{2}}\) is called mechanical advantage (MA)
Note:
High value of mechanical advantage means that a small effort can be used to lift a large load.
Examples for level

• See – saw
• Beam balance

1. Centre of gravity:
Centre of gravity of a body is that point through which the net gravitational force acts. The centre of gravity of a body may not be the same as its centre of mass. For a body of very large dimensions, the value of acceleration due to gravity is different for its different parts. In this situation the centre of gravity does not coincide with the centre of mass.

If the size of the body is small, the value of acceleration due to gravity is same for its different parts. In this situation, the centre of gravity of the body coincides with the centre of mass. Torque due to gravity.

Moment Of Inertia
A body at rest cannot rotate by itself. A body in uniform rotation cannot stop by itself. This inability of a material body is called rotational inertia. It depends on the mass of the body and axis of rotation. In other words it depends on a quantity called moment of inertia.

a. Moment of inertia of a particle:
Consider a particle of mass ‘m’ capable of rotation about an axis AB.

Let ‘r’ be the perpendicular distance of particle from AB. The moment of inertia of the particle about AB is defined as the product of mass of the particle and square of the distance between the particle and the axis of rotation.

b. Moment of inertia of a rigid body:

Consider a rigid body capable of rotation about an axis AB. Let the body consisting of particles of , masses, m₁, m₂, m₃……….m_n at distances r₁, r₂, r₃………..r_n
Then by definition, moment of inertia of m, about AB = m₁r₁².
M.I of m₂ about AB = m₂r₂²
————————–
M.I. of m_n about AB = m_nr_n²
Therefore total moment of inertia of the body about
I = m₁r₁² + m₂r₂² + ………………m_nr_n²

c. Moment of inertia of a ring about an axis through its centre and perpendicular to its plane:
Consider ring of mass M and radius R. AB the axis of rotation. Let ‘m’ be the mass of small section on the circumference of the ring.

M.I. of ‘m’about AB = mR²
∴ Total moment of inertia about AB,
I = ΣmR²

where Σm = M.

d. Moment of inertia of pair of small masses attached to the two ends of massless rod:
Consider a rigid massless rod of length / with a pair of small masses, rotating about an axis through the centre of mass perpendicular to the rod. Each mass M/2 is at a distance 1/2 from the axis of rotation.

∴ Total moment of inertia

Radius of gyration:
Radius of gyration of a body is the square root of ratio of moment of inertia and total mass of the body

Question 10.
Why do the concept of radius of gyration introduce?
Answer:
The moment of inertia of a body is given by
I = Σmr²
From the above equation it is clear that, we have to find the product of mass and the square of distances from the axis of rotation for all particles and then sum all these products. But the concept of radius of gyration simplifies the above problem.

In this method we find the centre of mass. Then we find a distance to any axis from this centre of mass, in such a way that the moment of inertia of this point (centre of mass) may be equal to that of I = Σmr². This distance from the axis of rotation to centre of mass is called radius of gyration. Practical utility of moment of inertia.

Question 11.
In a fly wheel (or) wheels of vehicles, most of the mass is concentrated at the rim? Explain why?
Answer:
(i) Flywheel:
The machines (such as steam engine, automobile engine etc) that produce rotational motion have a disc with large moment of inertia.

This disc is called fly wheel. Because of its large moment of inertia, the flywheel resists the sudden increase or decrease of the speed of the vehicle. It allows a gradual change in the speed and prevents the jerky motions. Thus fly wheel gives a smooth ride forthe passengers on the vehicle.

(ii) The wheels of vehicles:
The moment of inertia of wheels is increased by concentrating most of the mass at the rim of the wheel. If such a wheel gain or loses some K.E of rotation \(\left(\frac{1}{2} I \omega^{2}\right)\) brings a relatively smaller change in its angular speed w(∵ I is large) Hence such a flywheel helps in maintaining uniform rotation.

1. K.E of rotating body:
Consider a body rotating about an axis passing through some point O with uniform angular velocity ω. The body can be considered to be made up of a number of particles of masses m₁, m₂, m₃ etc.

At distances r₁, r₂, r₃ etc. All the particles will have same angular velocity ω. But their linear velocities will be different say v₁, v₂, v₃ etc.

Theorems Of Perpendicular And Parallelaxes
Theorem of perpendicular axes:
The moment of inertia of a planar body (lamina) about an axis perpendicular to its plane is equal to the sum of its moments of inertia about two perpendicular axes concurrent with perpendicular axis lying in the plane of the body.

(or)

Moment of inertia of a plane lamina about the z-axis is equal to sum of the moments of inertia about x axis and the y axis, if planer lamina lies in xy plane.
Explanation

Let I_x and I_y be the moments of inertia of the lamina about ox and oy. Let I_z be the moment of inertia of the lamina about an axis perpendicular to the lamina and passing through ‘0’ (about z axis) Then by perpendicular axis theorem.

Question 12.
M.l of disc about one of its diameters.
Answer:
According perpendicular axis theorem, I_z = I_x + I_y
But in case I_x = I_y
I_z = 2 I_x _____(1)
But we know I_z = MR²/2 _____(2)
sub(2) in (1), we get \(\frac{\mathrm{MR}^{2}}{2}\) = 2 I_x
I_x = \(\frac{M R^{2}}{4}\)
The moment of inertia about any diameter is \(\frac{M R^{2}}{4}\).

1. Theorem of parallel axis:
The moment of inertia of a body about any axis is equal to the sum of the moment of inertia of the body about a parallel axis passing through its centre of mass and the product of its mass and the square of the distance between the two parallel axes.

Explanation
Let I be the moment of inertia of a-body about an axisAB. Let I0 be moment of inertia about the axis CD parallel to AB and passing through the centre of gravity (G of the body). Let M be the mass of the body and ‘a’ be the distance between the two axes. Then by parallel axes theorem.
I = I_o + Ma²

Question 13.
What is the moment of inertia of rod of mass M, length l about an axis perpendicular to it through one end.

Answer:
Consider a rod of mass M and length l, rotating about an axis passing through one end. Let d_x be a small element at a distance x from the axis of rotation.
mass of the element dx, dm = \(\frac{M}{l}\)dx
∴ M.I of length small element, dl = \(\frac{M}{l}\) dx x²

Moment of inertia of a ring about a tangent:
Consider a ring of mass M and radius R. If this ring is rotating about tangent, we can use parallel axis theorem.
According to parallel axis theorem,

Kinematics Of Rotational Motion About A Fixed Axis
The quantities ‘q’, w and ‘α’ in rotational motion has corresponding quantities in translational motion (x, ‘v’ and a respectively). For translational motion, we have
v = u + at
v² = u² + 2as
s = ut+ \(\frac{1}{2}\) at²
putting u = w₁, v = w₂ and s = q, we get the equations of motion in rotational motion.
w₂ = w₁ + αt
ω₂² = ω₁² + 2αθ
θ = ω₁t + \(\frac{1}{2}\) αt²

Dynamics Of Rotational Motion About A Fixed Axis
Table 7.2 lists quantities associated with linear motion and their analogues in rotational motion.
a. Work done by a torque:

Consider a particle at P₁. Let r₁ be the position vector at time t = 0. This position vector makes an angle q with x – axis. Let particle be acted by a force \(\overrightarrow{\mathrm{F}}_{1}\). Due to this force the particle subtends an angle dq and reaches at p₁¹.

ds is the linear displacement due to the force \(\overrightarrow{\mathrm{F}}_{1}\) This force makes angle with α₁, the position vector r₁.f₁ is the angle made by \(\overrightarrow{\mathrm{F}}_{1}\) with linear displacement.
Form the triangle the workdone for small displacement ds,

Substituting the eq(2) in (1) we get
dW₁ = τ₁dθ
For rigid body, there are many particles. Hence total work done on it.
dW₁ = (τ₁ + τ₂ +……….)dθ

Where τ is the total torque acting oh the body.

b. Rateofwork done by torque:
Instantaneous power due to torque.
We know dw = τ dθ
dividing both sides by dt, we have \(\frac{d w}{d t}=\tau \frac{d \theta}{d t}\)
P = τω

c. Angular acceleration:
Rate of change of angular velocity is called angular acceleration.
Angular acceleration α = \(\frac{\mathrm{d} \omega}{\mathrm{dt}}\).

d. Relation between torque and angular acceleration:
The rate at which work is done on the body is equal to the rate at which kinetic energy increases.

τω = Iωα
τ = Iα
Note:
Just as force (F = ma) produces acceleration, torque produces angular acceleration in a body.
Newtons second law in rotation about a fixed axis

The angular acceleration is directly proportional to the applied torque and is inversely proportional to the moment of inertia of the body for rotation about a fixed axis.

Angular Momentum In Case Of Rotation About A Fixed Axis

Consider a rigid body rotating about a given axis with a uniform angular velocity w. Let the body consist of n particles of masses m₁, m₂, m₃…………m_n at perpendicular distances r₁, r₂, r₃………..r_n respectively from the axis of rotation.
If v₁, v₂, v₃…………v_n are the linear velocities of the
respective particles, then
v₁ = r₁w, v₂ = r₂w, v₃ = r₃w……….
The linear momentum of particle of mass m₁ is,
P₁ = m₁v₁
P₁ = m₁r₁w.
The angular momentum of this particle about the given axis,
l₁ = p₁ x r₁
= (m₁ v₁) x r₁
v₁ = r₁w
= m₁r₁²w
Similarly angular momentum of second particle
l₂ = m₂r₂²w
Angular momentum of the about the given axis,

1. Conservation of angular momentum:
Conservation of angular momentum and moment of inertia. When there is no external torque, the total angular momentum of a body or a system of bodies are a constant.

L = constant
But L = Iω
∴ Iω = a constant
Application

Question 14.
If the polar ice cap melts what will happen to the length of the day?
Answer:
For earth, angular momentum is a constant (Lw = constant, ie no torque acts on the earth). When the polar ice cap melts, the water thus formed will flow down to the equtorial region. The accumulation of water in equatorial line will increase the moment of inertia I of earth. In order to keep the angular momentum as a constant, w will decrease. The decrease in ‘w’ will increase the length of day.

Question 15.
If the earth loses the atmosphere what will happen to the length of the day?
Answer:
For earth, the angular momentum (L = Iw) is a constant, because there is no torque acting on it. When earth loses the atmosphere, I decreases and w increases to keep L as constant. Hence length of the day decreases.

Question 16.
A girl standing on a turn table. What happens to the rotation speed, if she stretches her hand?
Answer:
If a girl rotating with a uniform speed on turn table, it’s angular momentum (L = Iw) will be a constant. When she suddenly stretches her hand, I increases and w decreases to keep L as constant.

Question 17.
How does a circus acrobat and a divertake advantage of conservation of angular momentum?
Answer:
The diver while leaving the spring board, is throwing himself in a rotating, motion. When he brings his hands and legs close, I decrease and w increases. But before reaching water he will stretch his hands and legs. Hence I increases and w decreases. So that he gets a smooth entry into the water.

Rolling Motion

Question 18.
A wheel rolling uniformly along a level road is shown in the figure. The centre is moving with speed (V_CM). Find resultant velocities at P₁, P₂ and P₀.
Answer:
We know that the translational velocity of body is equal to the velocity of centre of mass. The velocity of centre of mass V_CM = Rw. Where R is the radius of wheel.
Velocity at P₁:
The point at P₁ has two velocities.

• Linear velocity (Vl)
• Translational velocity (Vt)

The linear velocity at P₁, V_l = Rw.
Translational velocity at P₁, V_t = Rw
[∵ translational velocities are same for all points on the wheel and its value equal to velocity of centre of mass].
The direction of V_l and V_t are same at P₁.
Hence total velocity at

Velocity at P₂:
Linear velocity at P₂, V_l = rw
[where r is the distance of P₂ from centre of mass]
translational velocity at P₂, V_t = Rw.
∴ Total velocity at

Velocity at P₀:
Linear velocity at P₀, \(\overrightarrow{\mathrm{V}}_{l}\) = Rω Translational at P₀, V_t = Rw.
The direction of V_land V_t are opposite.
∴ Hence total velocity,

= -Rw + Rw = 0
which means that the point P₀ is instantaneously at rest. Hence the friction at P₀ is zero. As a result rolling friction becomes less than the kinetic friction.
Note: The condition that P₀ is instantaneously at rest requires V_CM = Rw. Thus for the disc the condition for rolling without slipping is,
V_CM = RW.

1. Kinetic energy of rolling motion (without slipping):
In this case kinetic energy has two parts,

• due to the linear motion of centre of mass
• due to the rotational motion of the body.

K.E in terms of radius of gyration:
Moment of inertia I = mk²
where K is the radius of gyration of the body and v = Rw.
Substituting I, and V in eq(1), we get

Students can Download Chapter 6 Social Responsibilities of Business and Business Ethics Notes, Plus One Business Studies Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Business Studies Notes Chapter 6 Social Responsibilities of Business and Business Ethics

Contents
1. Social Responsibility – Meaning – Arguments for and against social responsibility – Kinds of social responsibility – Social responsibility towards different interest groups

2. Environmental protection – Causes of pollution – Need for pollution control – Role of business in environmental protection

3. Business Ethics – Meaning – Elements of Business Ethics Social responsibility of business refers to its obligation to take those decisions and perform those actions which are desirable in terms of the objectives and values of our society. Social responsibility involves an element of voluntary action on the part of business people for the benefit of society.

Arguments in favour of Social Responsibility:
1. Justification for Existence and Growth:
The prosperity and growth of business is possible only through continuous service to society.

2. Long term Interest of the firm:
A firm can improve its image and builds goodwill in the long run when its highest goal is to serve the society .

3. Avoidance of government regulations:
Business can avoid the problem of government regulations by voluntarily assuming social responsibilities.

4. Maintenance of society:
Law alone can’t help out people with ail the difficulties they face. A socially responsible business can contribute something for social peace and harmony.

5. Availability of resources with business:
Business has valuable financial and human resources which can be effectively used for solving problems of the society.

6. Better environment for doing business:
Social responsibility creates better environment for business operations as it improves quality of life and standard of living of the people.

7. Contribution to social problems:
Some of the social problems have been created by business firms themselves such as pollution, unsafe work places, discrimination etc, Therefore, it is the moral obligation of business to solve such social problems.

Arguments Against Social Responsibility:
1. Violation of profit maximization objective:
According to this argument, business exists only for the maximum profit to its shareholders and do not have responsibility to the society as a whole.

2. Burden on consumers:
Involvement of business in social responsibilities involve a lot of expenditure which will ultimately be borne by the customers.

3. Lack of Social Skills:
The business firms and managers are not expert to tackle the social problems like poverty, over population etc.

4. Lack of public support:
business cannot fulfill social responsibility because of lack of public confidence & cooperation.

Kinds of Social Responsibility:
1. Economic responsibility:
The primary social responsibility of a business is to produce goods and services that society wants and sell them at a profit.

2. Legal responsibility:
Every business has a responsibility to operate within the laws of the land.

3. Ethical responsibility:
This includes the behavior of the firm that is expected by the society but not included in law. eg: Respect religious sentiment and dignity of people while advertising.

4. Discretionary responsibility:
This refers to voluntary obligation that an enterprise assumes. eg: Giving charitable contributions to educational institutions, helping the people in natural calamities etc.

Social Responsibility towards different interest groups:
1. Responsibility towards share holders or owners:

• Provide a fair and regular return on the investment of shareholders.
• Provide regular and accurate information on the financial position of the firm.
• To ensure the safety of their investment.

2. Responsibility Towards the workers:

• Providing fair wages
• Providing good working conditions and welfare amenities.
• Respect democratic rights of workers to form unions.

3. Responsibility toward consumers:

• Supply right quality and quantity of goods and services at reasonable prices.
• Avoding unfair trade practices like adulteration, poor quality, misleading advertisement etc.
• Inform them about new products, its features, uses and other matters relating to the products.
• To handle the customers grievance promptly.

4. Responsibility Towards Government:

• Respect the laws of the country
• Pay taxes regularly and honestly.
• act according to the well accepted values of the society.

5. Responsibility towards community:

• Make employment opportunities
• Protect the environment from pollution.
• To uplift the weaker sections of society

Business & Environmental Protection Causes of Pollution:
Many industrial organisations have been responsible for causing air, water, land and noise pollution.
1. Air Pollution:
Air pollution is mainly due to Carbon monoxide emitted by automobiles and smoke and other chemicals from manufacturing plants. It has created a hole in the ozone layer leading to global warming.

2. Water pollution:
Water becomes polluted primarily from chemical and waste dumping.. It has led to the death of several animals and posed a serious problem to human life.

3. Land Pollution:
Dumping of toxic wastes reduces the quality of land and making it unfit for agriculture or plantation.

4. Noise Pollution:
Noise caused by the running of factories and vehicles create a serious health hazard such as loss of hearing, malfunctioning of the heart and mental disorders.

Need for Pollution Control:
1. Reduction of health hazard:
Pollution control measures can check diseases like cancer, heart attack & lung complications and support a healthy life on earth.

2. Reduced Risk of Liability:
It is a sound business policy to install pollution control devices in its premises to reduce the risk of liability of paying compensation to the affected people.

3. Cost Saving:
An effective pollution control programme is needed to save costs of operating business.

4. Improved Public Image:
A firm that adopts pollution control measures enjoys a good reputation as a socially responsible enterprise.

5. Other social benefits:
Pollution control results in many other benefits like clearer visibility, cleaner buildings, better quality of life, and the availability of natural products in a purer form.

Role of Business in Environmental Protection:

1. A definite commitment by top management to create a work culture for environmental protection
2. Ensuring that commitment of environmental protection is shared throughout the enterprise by all divisions and employees.
3. Developing clear cut policies and programmes for purchasing good quality raw materials, introducing superior technology, using scientific techniques of disposal of waste and developing employee skills for pollution control.
4. Complying with the laws and regulations enacted by the Government for prevention of pollution.
5. Participation in government programs relating to management of hazardous substances, cleaning up of polluted rivers, plantation of trees, and checking deforestation.
6. Periodical assessment of pollution control programmes in terms of costs and benefits with a view to improve them.
7. Arranging educational workshops and training materials to share technical information with everyone involved in pollution control.

Business Ethics:
Ethics is concerned with what is right and what is wrong in human behavior. Business ethics refer to the socially determined moral principles which should govern business activities.

Business ethics is the code of conduct followed and performed by every business. Ethical business behavior improves public image, earn’s public confidence and leads to greater success.
Examples of Business Ethics:

1. Charging fair prices from customers
2. Using fair weights for measurement of commodities
3. Giving fair treatment to workers
4. Earning reasonable profits.
5. Avoiding adulteration, hoarding etc.
6. Using environmentally friendly products

Elements of Business Ethics:
1. Top management commitment:
The Chief Executive Officer and higher level managers must give continuous leadership for developing and upholding the moral values of the organisation.

2. Publication of a Code:
‘Code’ refers to a formal written document of the principles, values and standards that guide a firm’s actions. It may cover the areas of fundamental honesty and adherence to laws, product safety and quality, health and safety in the workplace etc.

3. Establishment of Compliance Mechanism:
A suitable mechanism should be developed to comply with the ethical standards of the enterprise.

4. Employees Involvement:
To make ethical business a reality, employees at all levels must be involved.

5. Measuring Results:
Ethical results must be verified and audited that how far work is being carried according to ethical standards.

Students can Download Chapter 5 Emerging Modes of Business Notes, Plus One Business Studies Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Business Studies Notes Chapter 5 Emerging Modes of Business

Contents

• E-business – Meaning and scope of e-business – Differences between traditional and e-business – Benefits and Limitations of e-business
• Online transactions – Steps -e-business risk – Resources required for e-buisness
• Outsourcing – Meaning – features – Benefits and Concerns of outsourcing – Types of outsourcing services

e-Business (Electronic Business):
e-business may be defined as the conduct of industry, trade and commerce using the computer networks. Computer network means internet, e-business versus e-commerce e-business is a wider term which includes e-commerce and other electronically conducted business functions such as production, accounting, finance, personnel etc.

e-commerce covers a firms interactions with its customers and suppliers over the internet, e-business is, therefore, clearly much more than buying and selling over the internet, i.e., e-commerce.

Various constituents of e-business:
1. B2B Commerce:
It is that business activity in which two business units make electronic transaction.
Eg. making enquiries seeking or placing orders, communicating supply of goods, making payments, and so on.

2. B2C Commerce:
When the transaction is between business and consumers, it is called Business to Consumers. It enables a business firm to be in touch with its customers on round the clock basis. It involves consumers placing order on line, electronic payment etc.

3. Intra-B Commerce:
It means interaction and dealings among various departments and persons within the firm. For example, the marketing department may interact regularly with the production department and other departments that help in attaining efficient inventory handling, better cash management, timely and sufficient provision of customer services, and so on.

4. C2C Commerce:
Under it, both the parties involved in electronic transaction are customers. It is required for buying and selling of those goods for which there are no established markets. For example, selling used books and household equipments.

Benefits of e-Business:

1. e-business is relatively easy to start and requires lower capital.
2. Customers can buy goods at any time from any seller located in different parts of the world.
3. Business transactions can .be made easily and speedily.
4. It helps the business units to operate at the national as well as the global level.
5. It helps to reduce clerical and paper work.
6. It helps to eliminate middlemen.
7. Any company can launch its new product in the market through the medium of E-Business.
8. It improves the brand image of the company.

Limitations of e-Business:

1. It lacks personal touch with customers, which makes it unsuitable for medical, legal services etc.
2. The transaction can be finalised quickly, but physical delivery of goods often takes long time and be delayed.
3. For successful implementation of e business, the parties to the transactions have to be familiar with computers.
4. It leads to leakage of confidential information such as credit card details. Also there are problems of virus and hacking.
5. It is difficult to establish identity of the parties .

Differences between Traditional business and e-business:

On line Transactions:
On line transaction means receiving information about goods, placing an order, receiving delivery and making payment through medium of internet.

Buying / Selling Process:

Steps involved in online purchase:
1. Register with the online vendor by filling-up a registration form.

2. Place the order for the items put by customer in his virtual shopping cart, an on-line record of what has been picked up while browsing the Online store.

3. Payment for the purchases through online shopping may be done in a number of ways: i.e Cash on delivery, cheque, net banking transfer, debit/credit card.

Net Banking Transfer:
Modem banks provide to their customers the facility of electronic transfer of funds over the net. In this case, the buyer may transferthe transaction amount to the account of the online vendor who may, then, proceed to arrange for the delivery of goods.

Debit card:
The holder of a debit card can buy goods from approved shops without paying cash against the balance in his bank account. Every purchase reduces bank balance. Debit card is issued to bank account holders only and against the amount deposited with the bank.

Credit cards:
A credit card is an instrument issued by a bank in the name of the customer providing credit up to a specified amount. The person holding a valid credit card uses it for purchasing goods from approved shops without paying cash. The payment is made by the bank to the sellers. The buyers have to pay for the purchase within the credit period.

Security and safety of e- Business:
There are three types Of possible risks as listed below:
(a) Transaction risks:

1. Seller may deny that customer ever placed the order or the customer may deny that he ever placed the order. It is called “Default on Order taking/Giving”.
2. Goods may be delivered at wrong address or wrong goods may be delivered which is referred as “Default on Delivery”.
3. Seller may complaint that he didn’t receive payment while customer may claim that payment was over. This is referred as “Default
   Payment”.

(b) Data storage and transmission risks:

1. VIRUS (Vital Information & Resources Under Siege): Virus can disrupt functioning, damage the data and even may cause complete destruction of the system.
2. Interception: Data maybe intercepted in the course of transmission

(c) Risks of threat to intellectual property and privacy:

1. Once the information is made available over the internet, it moves out of the private domain. So important information may be copied by others.
2. When data furnished goes in the hands of others they may start dumping with lot of advertising & promotional literature into our e-mail box.

Resources Required for Successful e-Business Implementation:
The resources required for the e-Business are:

1. Computer system
2. Internet connection and technically qualified work force
3. A well developed web page
4. Effective telecommunication system
5. A good system for making payment using credit instruments.

Outsourcing or Business Process Outsourcing (BPO):
Outsourcing is a management strategy by which an organisation contracts out its major non-core functions to specialized service providers with a view to benefit from their expertise, efficiency and cost effectiveness, and allow managers to concentrate on their core activities.
Merits of outsourcing:

1. It provides an opportunity to the organisation to concentrate on areas in which it has core competency or strength.
2. It helps better utilisation of its resources as the management can focus its attention on selected activities and attain higher efficiency.
3. It helps the organisation to get an expert and specialised service at competitive prices. It helps in improved service and reduction in costs.
4. It facilitates inter-organisational knowledge sharing and collaborative learning.
5. It enables expansion of business as resources saved from outsourcing can be used for expanding the production capacity and diversified products.

Limitations of outsourcing

1. It reduces confidentiality as outsourcing involves sharing a lot of information with others.
2. It may be opposed by labour unions who feel threatened by possible reduction in their employment.
3. In the name of cost cutting, unlawful activities such as child labour, wage discrimination maybe encouraged in other countries.
4. The organisation hiring others may face the problem of loss of managerial control because it is more difficult to manage outside service providers than managing one’s own employees.
5. It causes unemployment in the home country.

Students can Download Chapter 6 Work, Energy and Power Notes, Plus One Physics Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Physics Notes Chapter 6 Work, Energy and Power

Summary
The Scalar Product

The scalar product (or) dot product of any two vectors \(\overrightarrow{\mathrm{A}}\) and \(\overrightarrow{\mathrm{B}}\) is defined as

Where ‘q’ is the angle between \(\overrightarrow{\mathrm{A}}\) and \(\overrightarrow{\mathrm{B}}\)
Note: The dot product of A and B is a scalar quantity. Geometrical meaning of \(\overrightarrow{\mathrm{A}}\) . \(\overrightarrow{\mathrm{B}}\)
We know \(\overrightarrow{\mathrm{A}}\) . \(\overrightarrow{\mathrm{B}}\) = ABcosθ
= A(Bcosθ)
= B(A cosθ)

Properties

Question 1.

Answer:

Work Energy Theory
Statement:
The change in kinetic energy of a particle is equal to the work done on it by the net force.
Proof:
We know v² = u² + 2as
v² – u² = 2as
Multiplying both sides with m/2; we get

Work
Definition:
The work done by the force is defined as the product of component of the force in the direction of the displacement and the magnitude of this displacement.
Explanation


Consider a constant force \(\overrightarrow{\mathrm{F}}\) acting on an object of mass m. The object undergoes a displacement d in the positive x direction as shown in the figure. The projection of \(\overrightarrow{\mathrm{F}}\) on d is Fcosθ.
Hence work done w = Fcosθ. d

There are three types of workdone

1. positive workdone
2. negative workdone
3. zero workdone

1. Positive workdone:
Work will be positive, if the displacement has a component in the direction of the force. The angle between force and displacement is zero for positive workdone.
When q = 0 w = Fd
Example

• A person carrying a load climbing up a staircase
• A body being pushed along a surface
• A body falling under gravitation force.

2. Negative workdone:
Work will be negative, if the displacement has a component opposite to the force F. The angle between force and displacement lies between 90° and 180°.
Example

• When a person carrying a load on his head climbs down a staircase, (applied force by him on the load is upwards and the displacement is opposite to it)
• When a body slides along a rough surface the displacement is opposite to the frictional force. Therefore the workdone by the frictional force is negative.

3. Zero work done:
Work will be zero, if there is no component along the direction of force. The angle between applied force and displacement is 90°.
Example
1. When a person carrying a load on his head walks along a level road, the displacement is perpendicular to the force and therefore the work done is zero.

2. In uniform circular motion the centripetal force is along the radius and direction of displacement is along the tangent.

Kinetic Energy
Kinetic energy is the energy possessed by the body because of it’s motion. Kinetic energy of a body of mass m and velocity v,

Workdone By Variable Force

Consider a body moving from x_i to x_f under a variable force. The variation of force with position is shown in graph. Consider a small AB = Dx. The force in this interval is nearly a constant.

Hence workdone to move a body from A to B is. Dw = F(x) Dx.F(x)dx gives the area of rectangle ABCD. When we add successive rectangular areas, we get total work as

When we take Dx tends to zero, the summation can be replaced integration.

Work Energy Theory For A Variable Force
Work energy theorem for a variable force can be derived from work energy theorem of constant force. According work energy theorem for constant force, Change in kE = work done
dk = dw
dk = F dx
Integrating from the initial position (x_i) to (x_f) we get

Concept Of Potential Energy
Potential energy of a body is the energy possessed by it because of its position.
Explanation
Considera mass ‘m’on the surface of the earth. If this mass is raised to height ‘h’ against force of gravity,
work done w = Force × displacement
w = mg × h
w = mgh
This work gets stored as gravitational potential energy.
ie; Gravitational energy V = mgh.

1. Relation between gravitational potential and gravitational force:
If we take negative of the derivative of V(h) with respect to height (h), we get

Where F is gravitational force. The above equation shows that gravitational force is the negative derivative of gravitational potential.

2. Relation between kinetic energy and gravitational potential energy:
Considera body of mass ‘m’ at a height ‘h’ from the surface of the earth. The potential energy at height h
pE = mgh ______(1)
If the body is allowed to fall from this height, it attains kinetic energy,
kE = \(\frac{1}{2}\)mv² _______(2)
But velocity at surface can be found from the formula
v² = u² + 2as
v² = 2gh [Since u = 0, a = g, s = h]
Substituting this value in eq(2), we get
kE = \(\frac{1}{2}\) m2gh
kE = mgh
kE = pE [∵ pE = mgh]

Properties of conservative force:

• A force is conservative, if it can be derived from a scalar quantity (ie F = – \(\frac{d V}{d x}\))
• The workdone by the conservative force depends only on the end points.
• The workdone by conservative force in a closed path is zero.

Conservation of mechanical energy for a freely falling body:

Consider a body of mass ‘m’ at a height h from the ground.
Total energy at the point A
Potential energy at A,
PE = mgh
Kinetic energy, KE = \(\frac{1}{2}\)mv² = 0
(since the body at rest, v = 0).
∴ Total mechanical energy = PE + KE = mgh + 0
= mgh.

Total energy at the point B
The body travels a distance x when it reaches B. The velocity at B, can be found using the formula.
v² = u² + 2as
v² = 0 + 2 gx
∴ KE at B, = \(\frac{1}{2}\)mv²
\(\frac{1}{2}\)m2gx
= mgx
P.E. at B, = mg (h – x)
Total mechanical energy = PE + KE
= mg (h – x) + mgx = mgh.

Total energy at C
Velocity at C can be found using the formula
v² = u² + 2as
v² = 0 + 2gh
∴ KE at C, = \(\frac{1}{2}\)mv²
\(\frac{1}{2}\)m2gh
= mgh
P.E. at C = 0
Total energy = PE + KE
= 0 + mgh = mgh.

The Potential Energy Of A Spring
Hooks law:
The restoring force developed in the spring is proportional to the displacement x and it is opposite to the displacement,
ie Fα – x

Where k is a constant called the spring constant.
Potential energy stored in a spring:

Consider a massless spring fixed to a rigid support at one end and a body attached to the other end. The body moves on a frictionless surface.

If a body is displaced by a distance dx, The work done for this displacement
dw = Fdx
∴ Total work done to move the body from x = 0 to x


This workdone is stored a potential energy in a spring. Hence potential energy of a spring.

Spring force is a conservative force:
If the spring is displaced from an initial position x_i to x_f and again to x_i;

W = 0
This zero workdone means that spring force is conservative.
Energy of a oscillating spring at any point:

If the block of mass ‘m’ (attached to massless spring) is extended to x_m and released, it will oscillate in between +x_m and -x_m. The total mechanical energy at any point x, (lies between -x_m and +x_m) is

This block mass ‘m’ has maximum velocity at equilibrium equi¬librium position (x = 0). At this position, the potential energy stored in a spring is completely converted in to kinetic energy.

Graphical variation of energy

The Law Of Conservation Of Energy
Statement:
Energy cannot be created or destroyed. It can be transformed from one form to another.

Question 2.
Prove conservation of energy for a freely falling body.
Answer:
Conservation of mechanical energy for a freely falling body:

Consider a body of mass ‘m’ at a height h from the ground.
Total energy at the point A
Potential energy at A,
PE = mgh
Kinetic energy, KE = \(\frac{1}{2}\)mv² = 0
(since the body at rest, v = 0).
∴ Total mechanical energy = PE + KE = mgh + 0
= mgh.

Total energy at the point B
The body travels a distance x when it reaches B. The velocity at B, can be found using the formula.
v² = u² + 2as
v² = 0 + 2 gx
∴ KE at B, = \(\frac{1}{2}\)mv²
\(\frac{1}{2}\)m2gx
= mgx
P.E. at B, = mg (h – x)
Total mechanical energy = PE + KE
= mg (h – x) + mgx = mgh.

Total energy at C
Velocity at C can be found using the formula
v² = u² + 2as
v² = 0 + 2gh
∴ KE at C, = \(\frac{1}{2}\)mv²
\(\frac{1}{2}\)m2gh
= mgh
P.E. at C = 0
Total energy = PE + KE
= 0 + mgh = mgh.

Various Form Of Energy
1. Heat:
Heat is a one form of energy, it is the internal energy of molecule.

2. Chemical energy:
Chemical energy arises from the fact that the molecules participating in the chemical reaction have different binding energies.

If the total energy of the reactants is more than the products of the reaction, heat is released and the reaction is said to be exothermic reaction. If the heat is absorbed in chemical reaction it is called endothermic.

3. Electrical energy:
The flow of electrons produce electric current.

4. The equivalence of mass and energy Mass and energy are equivalent and are related by the relation. E = mc², where C, the speed of light in. vacuum.

Question 3.
How much energy will be liberated, when 1 Kg. matter converts in to energy?
Answer:
Energy liberated E = mc²
E = 1 × (3 × 10⁸)²
= 9 × 10¹⁶J.

5. Nuclear energy:
Nuclear energy is obtained from the sun. In this case four light hydrogen nuclei fuse to form a helium nucleus, whose mass is less than the sum of the masses of the reactants. This mass difference (called the mass defect on) is the source of energy.

Power
Power is defined as the time rate at which work is done.

Expression for power in terms of F and V:
The work done (dw) by a force F for a displacement dr is


Where \(\overrightarrow{\mathrm{V}}\) is the instantaneous velocity when the force is \(\overrightarrow{\mathrm{F}}\).
Unit:
Unit of power is watt. 1 watt = 1J/S.
There is another unit of power, namely the horse power (hp)
1 hp = 746w
Kilowatt hour kwh:
Kilowatt hour (kwh) is the unit of energy used to mea-sure electrical energy. One kilowatt hour is the energy consumed in one hour at the rate of 1000 watts/ second.
1 kwh = 1000 watts × 60 × 60 seconds
= 3.6 × 106ws
1 kwh = 3.6 × 106J
Note : kwh is a unit of energy and not of power.

Collisions
There are two types of collisions.

1. Elastic collision
2. Inelastic collision

1. Elastic collision:
Elastic collision is one in which both momentum and kinetic energy are conserved.
Eg:

• collision between molecules and atoms
• collision between subatomic particles.

Characteristics of elastic collision:

• Momentum is conserved
• Total energy is conserved
• K. E. is conserved
• Forces involved during collision are conservative forces

2. Inelastic collision:
Inelastic collision is one in which the momentum is conserved, but KE is not conserved.
Example.

• Mud thrown on a wall
• Any collision between macroscopic bodies in every day life.

Characteristics of inelastic collision:

• Momentum is conserved
• Total energy is conserved
• K.E. is not conserved
• Forces involved are not conservative
• Part or whole of the KE is converted into other forms of energy like heat, sound, light etc.

2. Collisions in one Dimension:
If the initial velocities and final velocities of both the bodies are along the straight line, then it is called one dimensional motion.

Consider two bodies of masses m₁ and m₂ moving with velocities u₁ and u₂ in the same direction and in the same line. If u₁ > u₂ they will collide. After collision let v₁ and v₂ be their velocities.
By conservation of linear momentum.
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂ ______(1)
m₁u₁ – m₂u₂ = m₁v₁ – m₂v₂ ______(2)
This is an elastic collision, hence K.E. is conserved.

To find v₁ and v₂:


Discussion
Case -1 Mass of two bodies are equal
(i.e. m₁ = m₂ = m). Substitute these values in (7) and (8), we have

ie. bodies exchange their velocities.

Case – 2 (If u₂ =0 and m₂ >> m₁ ie; m₁ – m₂ ≈ -m₂, m₁ + m₂ ≈ -m₂)

The second body remains at rest while the first body rebounds with the same velocity.
Collisions in Two Dimensions:

Consider two bodies of masses m₁ and m₂ moving with velocities u₁ and u₂ along parallel lines. If u₁ > u₂ they will collide. Let v₁ and v₂ be their velocities after collision along directions θ₁ and θ₂. v₁ and v₂ can be resolved in to v₁ cosθ₁, v₂cosθ₂ parallel to x axis and v₁ sinθ₁ and v₂sinθ₂ parallel to y axis.
By conservation of momentum parallel to X-axis,

m₁u₁ + m₂u₂ = m₁v₁ cosθ₁ + m₂v₂ cosθ₂
By conservation of momentum parallel to y-axis.
m₁v₁sinθ₁ + m₂v₂ sinθ₂ = 0 + 0 = 0
By conservation of energy

Students can Download Chapter 12 Internet and Mobile Computing Notes, Plus One Computer Science Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Computer Science Notes Chapter 12 Internet and Mobile Computing

Summary
History of Internet:
Internet means international network of networks. The first form of Internet is ARPANET(Advanced Research Project Agency Network) started by US Department of Defence for their military during 1970’s. In 1989 a team lead by Tim Berners Lee introduced WWW(World Wide Web) by using the protocol HTTP. In 1998, Internet Corporation for Assigned Names and Numbers (ICANN) was established.

Internet:
It is a network of networks. It means that international network. We can transfer information between computers within nations very cheaply and speedily.

Intranet:
A private network inside a company or organisation is called intranet.

Extranet:
It allows vendors and business partners to access the company resources.

The hardware and software requirement for internet:

• A computer with a modem (internal/external)
• A telephone connection
• An account with an ISP
• A browser S/W eg: Internet Explorer or Mozilla…

Types of connectivity:
There are two ways to connect to the internet. First one dialing to an ISP’s computer or with a direct connection to an ISP.

Dial-up Connection:
Here the internet connection is established by dialing into an ISP’s computer. If ISP is not busy they verify the user name and password if it is valid they will connect our computer to the internet.lt uses Serial Line Internet Protocol (SLIP) or Point to Point Protocol (PPP). It is slower and has a higher error rate.

Direct connection:
In direct connection there is a fixed cable or dedicated phone line to the ISP. Here it uses ISDN (Integrated Services Digital Network) a high speed version of a standard phone line. Another method is leased lines that uses fibre optic cables.

Digital Subscribers Line (DSL) is another direct connection, this uses copper wires instead of fibre optic for data transfer. Direct connection provides high speed internet connection and error rate is less. Fibre To The Home(FTTH) uses optical fibers for data transmission.

Wireless broadband connectivity:
1. Mobile broadband:
Accessing Internet using wireless devices like mobile phones, tablet, USB dongles.

2. Wi MAX(Wireless Microwave Access):
It uses micro waves to transmit information across a network in a range 2 GHz to 11 GHz over very long distance.

3. Satellite broadband:
Accessing internet through satellite. A Very Small Aperture Terminal(VSAT) dish antenna and transceiver and modem are required at the user’s location. Expensive and high speed.

Internet access sharing methods:
One Internet connection can be shared among several computers using a LAN, Wi Fi or Li Fi.
1. Using LAN:
The Internet connection in a LAN can be shared among other computers in the network

2. Using Wi Fi(Wireless Fidelity):
It uses radio waves to transmit information across a network in a range 2.4 GHz to 5 GHz in short distance. Nowadays this technology is used to access internet in campuses, hyper markets, hotels by using Laptops, Desktops, tablet, mobile phones etc

3. Using Li Fi(Light Fidelity) network:
It is a fast optical(uses visible light for data transmission) version of Wi Fi. Its main component is a LED lamp that can transmit data and a photodiode that acts as a receiver.

Services on Internet:
1. www(World Wide Web):
This means this website address is unique and can be accessed each nook and corner of the world.

2. A browser is a piece of software that acts as an interface between the user and the internal working of the internet. With the help of a browser the user can search information on the internet and it allows user to navigate through the web pages. The different browsers are

• Microsoft internet explorer
• Mozilla Firefox
• Netscape Navigator
• Google Chrome
• Opera.

3. Web Browsing:

1. The browser determines the URL entered.
2. The browser asks the DNS for URLS corresponding IP address (Numeric address)
3. The DNS returns the address to the browser.
4. The browser makes a TCP connection using the IP address.
5. Then it sends a GET request for the required file to the server.
6. The server collects the file and send it back to the browser.
7. The TCP connection is released.
8. The text and the images in the web pages are displayed in the browser.

Search engines:
By using search engines we will get a variety of information. It is a newly developed tool that helped to search the information on the internet more effectively and easily. Search engines are programs that help people to locate information from crores of website on internet using a database that consists of references.

Users can interact with the search engine through the home page of the search engine. To get the information about artificial intelligence just type this in the box provided for it and click the search button. Search engines searches by using a particular search algorithm then displays the matching documents or web addresses.

Search engine use soft wares called spiders or bots to search documents and their web addresses. Spiders search the internet using the directions given by the search engines and prepare an index and stores it in a database. The searching algorithm searched this database when the users submits a request and create a web page displaying the matching results as hyperlinks.
eg: Google, Yahoo, Rediff etc.

E mail(Electronic mail):
It is used to send text, multi media messages between computers over internet. An example of an email id is [email protected]. Here jobi_cg is the user name, rediffmail is the website address and .com is the top level domain which identifies the types of the organisation. To send an email we require an email address. Some websites provide free email facility.

To send an email first type the recipients address and type the message then click the send button. The website’s server first check the email address is valid, if it is valid it will be sent otherwise the message will not be sent and the sender will get an email that it could not deliver the message.

This message will be received by the recipient’s server and will be delivered to recipient’s mail box. He can read it and it will remain in his mail box as long as he will be deleted. Simple Mail Transfer Protocol(SMTP) is used.
The email message contains the following fields:

1. To: Recipient’s address will be enter here. Multiple recipients are also allowed by using coma.
2. CC: Enterthe address of other recipients to get a carbon copy of the message.
3. bcc: The address to whom blind carbon copies are to be sent. This feature allows people to send copies to third recipient without the knowledge of primary and secondary recipients
4. From: Address of the sender
5. Reply to: The emait address to which replies are to be sent.
6. Subject: Short summary of the message.
7. Body: Here the actual message is to be typed.

The advantages of email are given below:

1. Speed is high
2. It is cheap
3. We can send email to multiple recipients
4. Incoming messages can be saved locally
5. It reduces the usage of paper
6. We can access mail box anytime and from anywhere.

The disadvantages are:

1. It requires a computer, a modem, software and internet connection to check mail.
2. Some mails may contain viruses
3. Mail boxes are filled with junk mail. So very difficult to find the relevant mail.

Social media:
Various social medias are Internet forums, social blogs, microblogs etc.

1. Internet forums: It is an online discussion site where people can exchange information about various issues like social, political, educational etc in the text form.
2. Social blogs: Conducting discussions about . particular subjects by entries or posts. eg: Blogger.com
3. Microblogs: It allows users to exchange short messages, multi media files etc. eg: www.twitter.com
4. Wikis: In this we can give our contributions regarding various topics. eg: www.wikipedia.org
5. Social networks: By using these web sites we can post our data and’ view others data. eg: www.facebook.com
6. Content communities: By using these websites we can share multi media files. eg: www.youtube.com

Advantages of social media:

1. Bring people together: It allows people to maintain the friendship
2. Plan and organize events: It allows users to plan and organize events.
3. Business promotion: It helps the firms to promote their sales.
4. Social skills: There is a key role of the formation of society.

Disadvantages:

1. Intrusion to privacy: Some people may misuse the personal information.
2. Addiction: sometimes it may waste time and money.
3. Spread rumours: The news will spread very quickly and negatively.

Cyber Security:
It is used to provide protection of valuable information such as credit card information from unauthorized access, intentional access, deletion, etc. while shopping on the internet.

Computer virus:
A virus is a bad program or harmful program to damage routine working of a computer system. It reduces the speed of a computer. It may delete the useful system files and make the computer useless.

Worm:
It is a stand alone malware program that replicates itself in order to spread to other computers. It slows down the traffic by consuming the bandwidth. In 2000 a worm called “ILOVEYOU” is affected many computers.

Trojan horse:
It appears as a useful software but it is a harmful software and it will delete useful software or files.

Spams:
Sending an email without recipient’s consent to promote a product or service is called spamming. Such an email is called a spam.

Hacking:
It is a process of trespassing computer networks. Two types white hats and black hats. White hats hack the computer networks to test the security but black hats intentionally stealing valuable data or destroying data.

Phishing (Fishing):
It is an attempt to get others information such as usenames, passwords, bank a/c details etc by acting as the authorized website. Phishing websites have URLs and home pages similar to their original ones and mislead others , it is called spoofing.

Denial of Service(DoS) attack:
Its main target is a Web server. Due to this attack the Web server/computer forced to restart and this results refusal of service to the genuine users. If we want to access a website first you have to type the web site address in the URL and press Enter key, the browser requests that page from the web server.

Dos attacks send huge number of requests to the web server until it collapses due to the load and stops functioning.

Man in the Middle attacks:
It is an attack in which an attacker secretly intercepts electronic messages send by the sender to the receiver and then modifies the message and retransmit it to the receiver.

To prevent this type of attack encrypted connections such as HTTPS(HTTP Secure), SFTP(Secure FTP) etc, must be used, that will be displayed in the URL.

Preventing network attacks
Firewall:
It is a system that controls the incoming and outgoing network traffic by analyzing the data and then provides security to the computer network in an organization from other network (internet).

Antivirus scanners:
It is a tool used to scan computer files for viruses, worms and Trojan horses and cure the infected system. If any fault found it stops the file from running and stores the file in a special area called Quarantine(isolated area) and can be deleted later.

Cookies:
Cookies are small text files that are created when we visit a website that keep track of our details. This information will help the hacker to use it for malicious purposes. It acts as a spyware.

Guidelines for using computers over internet:

• Emails may contain Viruses so do not open any unwanted emails
• Download files from reputed sources(sites)
• Avoid clicking on pop up Advt.
• Most of the Viruses spread due to the use of USB drives so use cautiously.
• Use firewall in your computer
• Use anti virus and update regularly
• Take backups in a regular time intervals

Mobile Computing:
The advancements in computing technology have led to the developments of more computing power in hand held devices like laptops, tablets, smart phones, etc. Nowadays people are able to connect to others through internet even when they are in move.

Mobile communication:
The term ‘mobile’ help the people to change their life styles and become the backbone of the society. Mobile communication networks do not require any physical connection.

Generations in mobile communication:
The mobile phone was introduced in the year 1946. Early stage it was expensive and limited services hence its growth was very slow. To solve this problem, cellular communication concept was developed in 1960’s at Bell Lab. 1990’s onwards cellular technology became a common standard in our country.
The various generations in mobile communication are
1.First Generation networks(1 G):
It was developed around 1980, based on analog system and only voice transmission was allowed.

2. Second Generation networks (2G):
This is the next generation network that was allowed voice and data transmission. Picture message and MMS(Multimedia Messaging Service) were introduced. GSM and CDMA standards were introduced by 2G.
(i) Global System for Mobile(GSM):
It is the most successful standard. It uses narrow band TDMA(Time Division Multiple Access), allows simultaneous calls on the same frequency range of 900 MHz to 1800 MHz. The network is identified using the SIM(Subscriber Identity Module).
(a) GPRS(General Packet Radio Services):lt is a packet oriented mobile data service on the 2G on GSM. GPRS was originally standardized by European Telecommunications Standards Institute (ETSI) GPRS usage is typically charged based on volume of data transferred. Usage above the bundle cap is either charged per megabyte or disallowed.

(b) EDGE(Enhanced Data rates for GSM Evolution):
It is three times fasterthan GPRS. It is used for voice communication as well as an internet connection.

(ii) Code Division Multiple Access (CDMA):
It is a channel access method used by various radio communication technologies. CDMA is an example of multiple access, which is where several transmitters can send information simultaneously over a single communication channel. This allows several users to share a band of frequencies To permit this to be achieved without undue interference between the users, and provide better security.

3. Third Generation networks(3G):
It allows high data transfer rate for mobile devices and offers high speed wireless broadband services combining voice and data. To enjoy this service 3G enabled mobile towers and hand sets required.

4. Fourth Generation networks(4G):
lt is also called Long Term Evolution(LTE) and also offers ultra broadband Internet facility such as high quality streaming video. It also offers good quality image and videos than TV.

Mobile communication services:
1. Short Message Service(SMS):
It allows transferring short text messages containing up to 160 characters between mobile phones. The sent message reaches a Short Message Service Center(SMSC), that allows ‘store and forward’ systems. It uses the protocol SS7(Signaling System No7). The first SMS message ‘Merry Christmas’ was sent on 03/12/1992 from a PC to a mobile phone on the Vodafone GSM network in UK.

2. Multimedia Messaging Service (MMS):
It allows sending Multi Media(text, picture, audio and video file) content using mobile phones. It is an extension of SMS.

3. Global Positioning System(GPS):
It is a space- based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. The system provides critical capabilities to military, civil and commercial users around the world.

It is maintained by the United States government and is freely accessible to anyone with a GPS receiver. GPS was created and realized by the U.S. Department of Defense (DoD) and was originally run with 24 satellites. It is used for vehicle navigation, aircraft navigation, ship navigation, oil exploration, Fishing, etc. GPS receivers are now integrated with mobile phones.

Smart Cards:
A smart card is a plastic card with a computer chip or memory that stores and transacts data. A smart card (may be like your ATM card) reader used to store and transmit data. The advantages are it is secure, intelligent and convenient. The smart card technology is used in SIM for GSM phones. A SIM card is used as an identification proof.

Mobile operating system:
It is an OS used in hand held devices such as smart phone, tablet, etc. It manages the hardware, multimedia functions, Internet connectivity,etc. Popular OSs are Android from Google,iOS from Apple, BlackBerry OS from Black Berry and Windows Phone from Microsoft.

Android OS:
It is a Linux based OS forTouch screen devices such as smart phones and tablets.lt was developed by Android Inc. founded in Palo Alto, California in 2003 by Andy Rubin and his friends. In 2005, Google acquired this. A team led by Rubin developed a mobile device platform powered by the Linux Kernel.

The interface of Android OS is based on touch inputs like swiping, tapping, pinching in and out to manipulate on screen objects. In 2007 onwards this OS is used in many mobile phones and tablets. Android SDK(Software Development Kit) is available to create applications(apps) like Google Maps, FB, What’s App, etc.

It is of open source nature and many Apps are available for free download from the Android Play Store hence increase the popularity.
Different Android Versions are shown below

Students can Download Chapter 11 Computer Networks Notes, Plus One Computer Science Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Computer Science Notes Chapter 11 Computer Networks

Summary
Computer network:
Two or more computers connected through a communication media that allows exchange of information between computers is called a Computer Network. Eg: Internet

Need for network:
The advantages of Networks are given below.
1. Resource sharing:
All the computers in a network can share software (programs, data ) and hardware (printer, scanner, CD drive, etc.).

2. Reliability:
If one computer fails, the other computer can perform the work without any delay. This is very important for banking, air traffic control and other application.

3. Price Vs Performance:
A main frame computer can be 10 times faster than a PC but it costs thousand times a PC. Therefore instead of a main frame 10 personal computers are used with less cost and same performance.

4. Communication Medium:
It is a powerful communication medium. We can exchange information between computers in a network.

5. Scalable:
This means, System performance can be increased by adding computers to a network.

Terminologies:

1. Bandwidth: The maximum amount of data that can be transmitted by the medium measured in Hertz.
2. Noise: It is the unwanted electrical or electromagnetic interferences that adversely affect the transmitted data signals.
3. Node: A computer or an I/O device connected to a network is called Node.

Data communication system:
Communication is the exchange of information between two human beings. But data communication is the exchange of information between two computers(devices).

1. Message: It is the data/information to be transmitted from one computer to another
2. Sender: It is a computer or a device that sends data. It is also called.source or transmitter
3. Receiver: It is a computer ora device that receives data
4. Medium: It is the path through which message transmitted from the sender to the receiver. There are two types Guided and Un Guided media.
5. Protocol: The rules and conventions for transmitting data.

Communication Medium:
There are two types guided and unguided.
Guided Media:
1. Twisted Pair cable:
2 types unshielded twisted pair and shielded twisted pair. Two copper wires individually insulated and twisted around each other and put in a plastic cover.

2. Coaxial cable:
A sturdy copperwire is insulated by plastic, it is covered just like a mesh by a conductor which is enclosed in an protective plastic coating. It is expenssive, less flexible and more difficult to install. But it is more reliable and carry for higher data rates.

3. Optical fibre:
These are made of glass fibres that are enclosed in a plastic jacket. It uses light instead of electrical signals. The light sources are LED or ILD.

Unguided Media:

1. Radio waves: It transmits data at different frequencies ranging from 3 kHz. to 300 GHz.
2. Microwaves: Microwave signals can travel in straight line if there is any obstacle in its path, it can’t bend. So it uses tall towers instead of short one.
3. Infrared waves: These waves are used for transmitting data in short distance and its frequency range is 300 GHz to 400 GHz.

Wireless communication technologies using:
radio waves
1. Bluetooth:
This technology uses radio waves in the frequency range of 2.402 GHz to 2.480 GHz. And transmit data in short distance. Mobile phones, Laptops, tablets etc use Bluetooth technology to transmit data.

2. Wi Fi(Wireless Fidelity):
It uses radio waves to transmit information across a network in a range 2.4 GHz to 5 GHz in short distance. Nowadays this technology is used to access internet in Laptops, Desktops, tablets, Mobile phones etc.

3. Wi MAX(Wireless Microwave Access):
It uses micro waves to transmit information across a network in a range 2 GHz to 11 GHz over very long distance.

4. Satellites:
By using satellite we can communicate from eny part of the world to any other. The ground stations are connected via the satellite. The data signals transmitted from earth to satellite (uplink) and from the satellite to the earth (downlink).

Data communication devices:
It acts as an interface between computer and the communication channel

Network Interface Card (NIC):
This device enables a computer to connect to a network and transmit information.

Hub:
It is a small, simple and inexpensive device used to connect computers(devices) to a network. If a computer wants to transmit data to another computer. First it sends to the hub, the hub retransmits this data to all other computers.

Each and every computer gets the data and check whether it is for them or not. It increases the network traffic and hence the transmission speed is low.

Switch:
It is an expensive device used to connect computers(devices) to a network. Unlike hub, switch transmit data not to all computers, it retransmits data only to the intended computer. So the traffic is less and speed is high

Repeater:
It is a device used to strengthen weak signals on the network.

Bridge:
It is a device used to link same type of networks.

Router:
It is similar to a bridge, but it can connect two networks with different protocols.

Gateway:
It is used to connect two different networks with different protocols.

Data terminal equipments:
These devices are used to control data flow to and from a computer

Modem:
It is a device used to connect the computer to the internet. It converts digital signal into analog signal (modulation) and vice versa (Demodulation)

Multiplexer:
It combines the inputs from different channels of a medium and produces one output.

Network topologies:
Physical or logical arrangement of computers on a network is called structure or topology. It is the geometrical arrangement of computers in a network. The major topologies developed are star, bus, ring, tree and mesh.
1. Star Topology:
A star topology has a server all other computers are connected to it. If computer A wants to transmit a message to computer B. Then computer A first transmit the message to the server then the server retransmits the message to the computer B.

That means all the messages are transmitted through the server. Advantages are added or remove workstations to a star network is easy and the failure of a workstation will not effect the other. The disadvantage is that if the server fails the entire network will fail.

2. Bus Topology:
Here all the computers are attached to a single cable called bus. Here one computer transmits all other computers listen. Therefore it is called broadcast bus. The transmission from any station will travel in both the direction.

The connected computers can hear the message and check whether it is for them or not. Advantages are add or remove computer is very easy. It requires less cable length and the installation cost is less. Disadvantage is fault detection is very difficult because of no central computer.

3. Ring Topology:
Here all the computers are connected in the shape of a ring and it is a closed loop. Here also there is no central computer. Here a computer transmits a message, which is tagged along with its destination computer’s address.

The message travels in one direction and each node check whether the message is for them. If not, it passes to the next node. It requires only short cable length. If a single node fails, at least a portion of the network will fail. To add a node is very difficult.

4. Hybrid Topology:
It is a combination of any two or more network topologies. Tree topology and mesh topology can be considered as hybrid topology.
(a) Tree Topology:
The structure of a tree topology is the shape of an inverted tree with a central node and branches as nodes. It is a variation of bus topology. The data transmission takes place in the way as in bus topology. The disadvantage is that if one node fails, the entire portion will fail.

(b) Mesh Topology:
In this topology each node is connected to more than one node. It is just like a mesh (net). There are multiple paths between computers. If one path fails, we can transmit data through another path.

Types of networks:
The networks are classified into the following based upon the amount of geographical area that covers.
(i) Personal Area Network(PAN):
It is used to connect devices situated in a small radius by using guided media or unguided media

(ii) Local Area Network (LAN):
This is used to connect computers in a single room, rooms within a building or buildings of one location by using twisted pair wire or coaxial cable. Here the computers can share Hardware and software. Data transferrate is high and error rate is less, eg: The computers connected in a school lab.

(iii) Metropolitan Area Network (MAN):
A Metropolitan Area Network is a network spread over a city. For example a Cable TV network. MAN have lesser speed than LAN and the error rate is less. Here optical fiber cable is used.

(iv) Wide Area Network (WAN):
This is used to connect computers over a large geographical area. It is a network of networks. Here the computers are connected using telephone lines or Micro Wave station or Satellites. Internet is an example for this.

LAN and MAN are owned by a single organization but WAN is owned by multiple organization. The error rate in data transmission is high.

Logical classification of networks:
Peer to peer:
In this configuration all the computers have equal priority. That means each computer can function as both a client and a server. There is no dedicated server.

Client-Server:
In this configuration a computer is powerful which acts as a dedicated server and all others are clients (work stations). A Server fulfils the needs of the clients.

1. File Server: A computer that stores and manages files for other devices on a network
2. Web Server: A computer that handles the requests for web pages.
3. Print Server: A computer that handles the print jobs from other computers on a network.
4. Database Server: A computer that manages the database.

Network protocols:
A protocol is a collection of rules and regulations to transfer data from one location to another. Transmission Control Protocol (TCP), which uses a set of rules to exchange messages with other Internet points at the information packet level. Internet Protocol (IP), which uses a set of rules to send and receive messages at the Internet address level
1. FTP:
File Transfer Protocol which is used for transferring files between computers connected to local network or internet.

2. HTTP:
is a protocol used for WWW for enabling the web browse to access web server and request HTML documents.

3. DNS (Domain Name System):
When we type web sites address in the address bar, the browser determines the URL and asks the DNS for URLS corresponding IP address (Numeric address). The DNS returns the address to the browser.

Identification of computers over a network:
A computer gets a data packet on a network, it can identify the sender’s address easily. It is similar to our snails mail, each letter is stamped in sender’s post office as well as receiver’s post office.

Media Access Control(MAC) address:
It is a unique 12 digit hexadecimal number(IMEI for mobile phones, it is a 15 digit decimal number) assigned to each NIC by its manufacturer. This address is known as MAC address and its permanent. It is of the form. MM:MM:MM:SS:SS:SS.

The first MM:MM:MM contains the ID number of the adapter company and the second SS:SS:SS represents the serial number assigned to the adapter by the company.

Internet Protocol (IP) address:
An IP address has 4 parts numeric address. Each parts contains 8 bits. By using 8 bits we can represent a decimal number between 0 to 255(28 = 256 numbers). Each part is separated by dot. A total of 4 × 8 = 32 bits used. But nowadays 128 bits are used for IP address.

Uniform Resource Locator(URL):
Every resource on the internet has a unique URL. Mainly it has three parts
eg: http://www.hscap.kerala.gov.in /index.html.

• http: http means hypertext transfer protocol. It is a protocol used to transfer hypertext.
• www: World Wide Web. With an email address we can open our mail box from anywhere in the world.
• hscap.kerala: It is a unique name. It is the official website name of Single Window System
• gov: It is the top level domain. It means that it is a government organization’s website.
• in: It is the geographical top level domain. It represents the country, in is used for India.
• index.html: It represents the file name.

Top Level Domain Names:

• .com The site register for commercial purpose
• .edu The site register for educational purpose
• .gov The site register by Government agencies
• .mil The site register for military services
• .net The site register for network purpose
• .org The site register by organizations

Country Specific Domain Names:

• .in India
• .au Australia
• .ca Canada
• .ch China
• .jp Japan
• .us United States of America

Students can Download Chapter 10 Functions Notes, Plus One Computer Science Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Computer Science Notes Chapter 10 Functions

Concept of modular programming:
The process of converting big and complex programs into smaller programs is known as modularisation. This small programs are called modules or sub programs or functions. C++ supports modularity in programming called functions
Merits of modular programming:

• It reduces the size of the program
• Less chance of error occurrence
• Reduces programming complexity
• Improves reusability

Demerits of modular programming:
While dividing the program into smaller ones extra care should be taken otherwise the ultimate result will not be right.

Functions in C++:
Some functions that are already available in C++ are called pre-defined or built in functions. In C++, we can create our own functions for a specific job or task, such functions are called user defined functions. A C++ program must contain a main() function. A C++ program may contain many lines of statements(including so many functions) but the execution of the program starts and ends with main() function.

Pre-defined functions:
To invoke a function that requires some data for performing the task, such data is called parameter or argument. Some functions return some value back to the called function.

String functions:
To manipulate string in C++ a header file called string.h must be included.
1. strlen():
to find the number of characters in a string(i.e. string length).
Syntax: strlen(string);
eg:
cout<<strien(“Computer”); It prints 8.

2. strcpy():
It is used to copy second string into first string.
Syntax: strcpy(string1, string2);
eg:
strcpy(str,”BVM HSS”);
cout<<str; It prints BVM HSS.

3. strcat():
It is used to concatenate second string into first one.
Syntax: strcat(string1,string2)
eg:
strcpy(str1,’’Hello”);
strcpy(str2,” World”);
strcat(str1 ,str2);
cout<<str1; It displays the concatenated string “Hello World”

4. strcmp():
It is used to compare two strings and returns an integer.
Syntax: strcmp(string1,string2)

• if it is 0 both strings are equal.
• if it isgreaterthan 0(i.e. +ve) stringl is greater than string2
• if it is less than 0(i.e. -ve) string2 is greater than stringl

eg:
#include<iostream>
#include<cstring>
using namespace std;
int main()
{
char str1 [10],str2[10];
strcpy(str1,”Kiran”);
strcpy(str2,”Jobi”);
cout<<strcmp(str1 ,str2);
}
It returns a +ve integer.

5. strcmpi():
It is same as strcmpO but it is not case sensitive. That means uppercase and lowercase are treated as same.
eg: “ANDREA” and “Andrea” and “andrea” these are same.
#include<iostream>
#include<cstring>
using namespace std;
int main()
{
char str1 [10],str2[10];
strcpy(str1,”Kiran”);
strcpy(str2,”KIRAN”);
cout<<strcmpi(str1 ,str2);
}
It returns 0. That is both are same.

Mathematical functions:
To use mathematical functions a header file called math.h must be included.
1. abs():
To find the absolute value of an integer.
eg: cout<<abs(-25); prints 25.
Cout<<abs(+25); prints 25.

2. sqrt():
To find the square root of a number.
eg: cout<<sqrt(49); prints 7.

3. pow():
To find the power of a number.
Syntax. pow(number1, number2)
eg: cout<<pow(2,10); It is equivalent to 210. It prints 1024.

4. sin():
To find the sine value of an angle and the angle must be in radian. To convert an angle into radian multiply by 3.14(“) and divide by 180.
float x = 60 × 3.14/180;
cout<<sin(x); prints 0.86576.

5. cos():
To find the cosine value of an angle and the angle must be in radian. To convert an angle into radian multiply by 3.14(“) and divide by 180.
float x = 60 × 3.14/180;
cout<<cos(x); prints 0.50046.

Character functions:
To manipulate character in C++ a header file called ctype.h must be included.
1. isupper():
To check whether a character is in uppercase or not. If the character is in uppercase it returns a value 1 otherwise it returns 0.
Syntax: isupper(charch);

2. islower():
To check whether a character is in lowercase or not. If the character is in lowercase it returns a value 1 otherwise it returns 0.
Syntax: islower(char ch);

3. isalpha():
To check whether a character is an alphabet or not. If the character is an alphabet it returns a value 1 otherwise it returns 0.
Syntax: isalpha(char ch);

4. isdigit():
To check whether a character is a digit or not. If the character is a digit it returns a value 1 otherwise it returns 0.
Syntax: isdigit(charch);

5. isalnum():
To check whether a character is an alphanumeric or not. If the character is an alphanumeric it returns a value 1 otherwise it returns 0.
Syntax: isalnum(char ch);

6. toupper():
It is used to convert the given character into uppercase.
Syntax: toupper(char ch);

7. tolower():
It is used to convert the given character into lowercase.
Syntax: tolower(char ch);

Conversion functions:
Some occasions we have to convert a data type into another for this conversion functions used. The header file stdlib.h must be included.
1. itoa():
It is used to convert an integer value to string type.
Syntax: itoa(int v, char str, int size); This function has 3 arguments, first one is the integer to be converted, second is the string variable to store and third is the size of the string.
eg: itoa(“123”,str,4);
cout<<str;

2. atoi():
It Is the opposite of itoa( ). That is it converts a string into integer.
Syntax: atoi(str);

I/O Manipulating function:
It is used to manipulate I /O operations in C++. The header file iomanip.h must be included,
(a) setw(): It is used to set the width for the subsequent string.
Syntax: setw(size);

User defined functions:
Syntax: Return type Function_name(parameterlist)
{
Body of the function
}

• Return type: It is the data type of the value returned by the function to the called function;
• Function name: A name given by the user.

Different types of User defined functions.

• A function with arguments and return type.
• A function with arguments and no return type.
• A function with no arguments and with return type.
• A function with no arguments and no return type.

Prototype of functions:
Consider the following codes
Method 1:
#include<iostream>
using namespace std;
int sum(int n1,int n2)
{
return(n1 + n2);
}
int main()
{
int n1 ,n2;
cout<<“Enter 2 numbers:”;
cin>>n1>>n2;
cout<<“The sum is “<<sum(n1,n2);
}

Method 2:
#include<iostream>
using namespace std;
int main()
{
int n1 ,n2;
cout<<“Enter 2 numbers:”;
cin>>n1>>n2;
cout<<“The sum is “<<sum(n1,n2);
}
int sum(int n1 ,int n2)
{
return(n1 + n2); ‘
}
In method 1 the function is defined before the main function. So there is no error. In method 2 the function is defined after the main function and there is an error called “function sum should have a prototype”.

This is because of the function is defined after the main function. To resolve this a prototype should be declared inside the main function as follows.

Method 3:
#include<iostream>
using namespace std;
int main()
{
int n1,n2;
int sum(int.int);
cout<<“Enter 2 numbers:”;
cin>>n1>>n2;
cout<<“The sum is “<<sum(n1,n2);
}
int sum(int n1,int n2)
{
retum(n1 + n2);
}

Functions with default arguments:
We can give default values as arguments while declaring a function. While calling a function the user doesn’t give a value as arguments the default value will be taken. That is we can call a function with or without giving values to the default arguments.

Methods of calling functions:
Two types call by value and call by reference.
1. Call by value:
In call by value method the copy of the original value is passed to the function, if the function makes any change will not affect the original value.

2. Call by reference:
In call by reference method the address of the original value is passed to the function, if the function makes any change will affect the original value.

Scope and life of variables and functions:
1. Local scope:
A variable declared inside a block can be used only in the block. It cannot be used any other block.
eg:
#include<iostream>
using namespace std;
int sum(int n1,int n2)
{
int s;
s = n1 + n2;
return(s);
}
int main()
{
int n1,n2;
cout<<“Enter 2 numbers:”;
cin>>n1>>n2;
cout<<“The sum is “<<sum(n1,n2);
}
Here the variable s is declared inside the function sum and has local scope;

2. Global scope:
A variable declared outside of all blocks can be used any where in the program.
#include<iostream>
using namespace std;
int s;
int sum(int n1,int n2)
{
s = n1 + n2;
return (s);
}
int main()
{
int n1 ,n2;
cout<<“Enter 2 numbers :”;
cin>>n1>>n2;
cout<<“The sum is “<<sum(n1 ,n2);
}
Here the variable s is declared out side of all functions and we can use variable s any where in the program

Recursive functions:
A function calls itself is called recursive function.

Students can Download Chapter 9 String Handling and I/O Functions Notes, Plus One Computer Science Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Computer Science Notes Chapter 9 String Handling and I/O Functions

Summary
String handling using arrays:
A string is a combination of characters hence char data type is used to store string. A string should be enclosed in double quotes. In C++ a variable is to be declared before it is used.Eg. “BVM HSS KALPARAMBU”.

Memory allocation for strings:
To store “BVM” an array of char type is used. We have to specify the size. Remember each and every string is end with a null (\0) character. So we can store only size- 1 characters in a variable. Please note that \0 is treated as a single character. \0 is also called as the delimiter.
char school_name[4]; By this we can store a maximum of three characters.

Consider the following declarations

• char my_name[10] = ”Andrea”;
• char my_name2[ ] = ”Andrea”;
• char str[ ] = ”Hello World”

In the first declaration 10 Bytes will be allocated but it will use only 6 + 1 (one for ‘\0’) = 7 Bytes the remaining 3 Bytes will be unused. But in the second declaration the size of the array is not mentioned so only 7 Bytes will be allocated and used hence no wastage of memory.

Similarly in the third declaration the size of the array is also not mentioned so only 12( one Byte for space and one Byte for ‘\0’) Bytes will be allocated and used hence no wastage of memory

Input/output operations on strings:
Consider the following code
#include<iostream>
using namespace std;
int main()
{
char name[20];
cout<<“Enter your name:”;
cin>>name;
cout<<“Hello “<<name;
}
If you run the program you will get the prompt as follows
Enter your name: Alvis Emerin
The output will be displayed as follows and the “Emerin” will be truncated.
Hello Alvis
This is because of cin statement that will take upto the space. Here space is the delimiter. To resolve this gets() function can be used. To use gets() and puts() function the header file stdio.h must be included. gets() function is used to get a string from the keyboard including spaces.

puts() function is used to print a string on the screen. Consider the following code snippet that will take the input including the space.
#include<iostream>
#include<cstdio>
using namespace std;
int main()
{
char name[20];
cout<<“Enter your name:”;
gets(name);
cout<<“Hello “<<name;
}

More console functions:

Stream functions for I / O operations:
Somefunctions that are available in the header file iostream.h to perforrn I/O operations on character and strings(stream of characters). It transfers streams of bytes between memory and objects. Keyboard and monitor are considered as the objects in C++.

Input functions:
The input functions like get( )(to read a character from the keyboard) and getline() (to read a line of characters from the keyboard) is used with cin and dot(.) operator.

eg:
#include<iostream>
using namespace std;
int main()
{
char str[80],ch=’z’;
cout<<“enter a string that end with z:”;
cin.getline(str,80,ch);
cout<<str;
}
If you run the program you will get the prompt as follows
Enter a string that end with z: Hi I am Jobi. I am a teacher. My school is BVM HSS The output will be displayed as follows and the string after ‘z’ will be truncated.
Hi, I am Jobi. I am a teacher

Output function:
The outputt functions like put() (to print a character on the screen) and write() (to print a line of characters on the screen) is used with cout and dot(.) operator.

Students can Download Chapter 8 Arrays Notes, Plus One Computer Science Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Computer Science Notes Chapter 8 Arrays

Summary
An array is a collection of elements with same data type Or with the same name we can store many elements, the first or second or third, etc can be distinguished by using the index(subscript). The first element’s index is 0, the second elements index is 1, and so on.

Declaring arrays:
Suppose we want to find the sum of 100 numbers then we have to declare 100 variables to store the values. It is a laborious work. Hence the need for array arises.
Syntax: data_type array_name[size];
To store 100 numbers the array declaration is as follows
int n[100]; By this we store 100 numbers. The index of the first element is 0 and the index of last element is 99.

Memory allocation for arrays:
The amount of memory requirement is directly related to its type and size,

• int n[100]; It requires 2Bytes(for each integer) × 100 = 200 Bytes.
• float d[100]; It requires 4Bytes(for each float) × 100=400 Bytes.

Array initialization:
Array can be initialized in the time of declaration. eg: int age[4] = {16, 17, 15, 18};

Accessing elements of arrays:
Normally loops are used to store and access elements in an array.
eg:
int mark[50], i;
for(i=0;i<50;i++)
{
cout<<“Enter value for mark”<<i+1;
cin>>mark[i];
}
cout<<“The marks are given below:”;
for(i=0;i<50;i++)
cout<<mark[i];

Array operations:
Traversal:
Accessing all the elements of an array is called traversal.

Sorting:
Arranging elements of an array in an order(ascending or descending)
1. Bubble sort:
It is a simple sorting method. In this sorting considering two adjascent elements if it is out of order, the elements are interchanged. After the first iteration the largest(in the case of ascending sorting) or smallest(in the case of descending sorting) will be the end of the array. This process continues.

2. Selection sort:
In selection sort the array is divided into two parts, the sorted part and unsorted part. first smallest element in the unsorted part is searched and exchanged with the first element. Now there is 2 parts sorted part and unsorted part. This process continues.

Searching:
It is the process of finding the position of the given element.
1. Linear search:
In this method each element of the array is compared with the element to be searched starting from the first element. If it finds the position of the element in the array is returned.

2. Binary search:
It uses a technique called divide and conquer method. It can be performed only on sorted arrays. First we check the element with the middle element. There are 3 possibilities. The first possibility is the searched element is the middle element then search can be finished.

The second possibility is the element is less than the middle value so the upper bound is the middle element. The third possibility is the element is greater than the middle value so the lower bound is the middle element. Repeat this process.

Two dimensional (2D) arrays:
Some occasions we have to store 6 different marks of 50 students. For this we use 2D arrays. An array with two subscripts is used.
eg: int mark[r][c]; Here r is the row and c is the column.

Declaring 2D arrays:
Syntax: datatype array_name[rows][columns];
The elements of this array is referred as mark[0][0], mark[0][1], mark[r – 1][c – 1].
eg: int m[5][5]; This array can store 5 × 5 = 25 elements.

Matrices as 2D arrays:
Matrix is a concept in mathematics that can be represented by 2D array with rows and columns. A nested loop(a loop contains another loop) is used to store and access elements in an array.

Multi-dimensional arrays:
3 Dimensional(3D) array is an example for this.
Syntax: data_type array_name[size1 ][size2][size3];
eg: int m[5][5][5]; This array can store 5 × 5 × 5 = 125 elements.