Kerala Syllabus 10th Standard Social Science Solutions Part 2 Chapter 2 In search of the Source of Wind

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Kerala State Syllabus 10th Standard Social Science Solutions Part 2 Chapter 2 In search of the Source of Wind

In search of the Source of Wind Text Book Questions and Answers

Social Science Class 10 Kerala Syllabus Question 1.
Did you notice the places marked A and B in the diagram? Which of these places will have a higher atmospheric pressure? Why?

Answer:
The place marked B will have a higher atmospheric pressure, because atmospheric pres-sure decreases with altitude.

Sslc History Chapter 1 Notes Pdf Kerala Syllabus Question 2.
Why do mountaineers carry oxygen cylinders ?
Answer:
When height increases the amount of air decreases in atmosphere. So mountaineers carry oxygen cylinders.

Sslc Geography Chapter 1 Notes Kerala Syllabus Question 3.
Compare the two pictures. Identify the situations of low and high atmospheric pressure and suitably mark ‘H’ and ‘I? in the pictures.
Answer:
During day time air gets heated. So the density of the air decreases. Then he weight of the air decreases. It causes decrease in pressure

Sslc History Chapter 1 Malayalam Medium Kerala Syllabus Question 4.
Compared to the colder regions, the tropical regions experience low atmospheric pres¬sure why?
Answer:
Very high temperature experienced in lower latitude so air starts to rise. That leads to low atmospheric pressure. But in a colder region air is dense so that leads to high atmospheric pressure.

Sslc History Chapter 1 Notes English Medium Kerala Syllabus Question 5.
Two places at the same elevation are marked as A and B in the figure. Which of these has a low atmospheric pressure? Why?

Answer:
A located in the coastal area, B is located away from the coastal area. Humidity in the atmosphere of the region near coastal area will be more, the the atmospheric pressure will be less here. So A has a low atmospheric pressure

Kerala Syllabus 10th Standard Social Science Notes Question 6.
Observe the distribution of isobars in the given figure and mark the places experiencing high pressure and low pressure as H and L respectively.
Answer:

10th Standard Social Science Notes Kerala Syllabus Question 7.
Find out the position of the sub tropical high pressure belt from the given figure (Text-book fig 2.5).
Answer:
Situated on 30° latitude of North and’South hemisphere.

Sslc Social Science Chapter Wise Questions Kerala Syllabus Question 8.
Find out the location of the sub polar low pressure belt from Fig (Textbook fig 2.5).
Answer:
Situated on 60° latitude of North and South hemisphere.

Question 9.
If the earth did not rotate, would there have been low pressure in the sub polar region ?
Answer:
No, Besides if the earth did not rotate the direction of the winds would be another.

Question 10.
Find out the latitudinal location of the polar high pressure belts.
Answer:
90° North and South

Question 11.
Based on different types of pressure belts and their latitudes
Answer:

Pressure belts	Latitudinal extent
Equatorial low pressure belt	5° N and S of the equator
Sub tropical high pressure belt	30° N and S of the equator
Sub polar low pressure belt	60° N and S of the equator
Polar high pressure belt	90° poles on both South and North hemisphere

Question 12.
Mark the direction of winds in both the diagrams, using arrow marks.
In which of these situations will the speed of the wind be higher? Why?

Answer:
The speed of the wind will be higher in diagram A. In this diagram, isobars are depicted closely in diagram B the distance between isobars is more. So the speed of the wind will be less.

Question 13.
Find out the direction and the name of the trade winds in the Southern Hemisphere from Fig 2.9.
Answer:
Direction: South east
Name : South east trade winds

Question 14.
What could be the reason for the trade winds blowing from south east and north east directions?
Answer:
Trade wind blows from sub-tropical high pressure belts to the equatorial low pressure belts. It is due to the Coriolis effect that the direction of trade winds is from north east in northern hemisphere and southeast in the southern hemisphere.Otherwise it will be from exact north and south.

Question 15.
Identify and note the direction of the westerlies in both the hemispheres from Fig 2.9.
Answer:
In northern hemisphere direction of westerlies is mostly from the west to north. In southern hemisphere direction of westerlies from west to south.

Question 16.
Prepare a chart describing the planetary winds, the areas where they blown and their features.
Answer:

Question 17.
Find out from the atlas the countries along the southern slope of the Alps.
Answer:
Italty, Slovania

Question 18.
Prepare a report on the distress caused by Ockhi and suggest measures to mitigate the impact of such disasters in future by collecting information from internet and other sources.
Answer:
Based on the climatic region of their formation, cyclones can be classified as tropical cyclones and temperate cyclone. Cyclones often cause extensive damage and destruction wherever they occur. The Ockhi cyloninc winds that struck the coastlines of Kerala and Lakshdweep during November 2017.

This was a tropical cyclone. Tropical cylones are caused due to local pressure differences in the tropical oceans, especially the Indian ocean.Ockhi cyclones left the Indian coasts after wreaking havoc on life and property. While near Kanyakumari in mainland India, Cyclone Ockhi changed course and intensified while heading towards Lakshadweep in the Arabian Sea.

Ockhi impacted Lak-shadweep on December 2, uprooting coconut trees and causing extensive damage to houses, power lines and other infrastructure on the islands. Ockhi weakened into a well- marked low near the south coast of Gujarat, India, on December 6, before crossing the coastline and dissipating shortly afterward. In its entirety, Cyclone Ockhi left a trail of massive destruction in Sri Lanka, Lakshadweep, South India, and The Maldives, as it strengthened from a depression to a mature cyclone.

Though it rapidly weakened during its final stages over the Arabian Sea, it caused heavy rainfall along the western coast of India, particularly in Maharashtra and Gujarat. Ockhi caused at least 245 fatalities, including 218 in India and 27 in Sri Lanka, and the storm left at least 550 people missing, mainly fishermen.

Weather forecasting offices has given a warning that Okhi cyclone can travel at a speed of 120 Kilometers. If cyclones like Okhi are reported never ignore such news and take necessary precautions. If the offices give introduction to shift from your houses, obey the orders, fisherman have to be cautious.

Question 19.
Complete the following flow chart showing the classification of winds.

In search of the Source of Wind Let Us Assess

Question 1.
Temperature, altitude and humidity are inversely proportional to atmospheric pressure. Justify?
Answer:
When temperature increases air gets heated and expands. The expanded air is less dense and it ascends. This leads to lowering of pressure. When temperature decreases, air becomes dense and descends.

This will increase atmospheric pressure. So there is an inverse relationship between temperature and pres sure. When altitude increases air becomes rarefied. So it exerts less pressure. But when altitude decreases earth gravity pulls the gas molecules towards the ground.

So air becomes dense and it exert high pressure. Humidity means the amount of water vapor present in the atmosphere. Water vapor is lighter than air. If the amount of water vapor is more in a unit volume of air, then atmospheric pressure will be less because moist air contains less oxygen and nitrogen and exerts less pressure.While dry air exerts high pressure as it contains more oxygen and nitrogen.

Question 2.
Prepare notes on the role of solar energy and the earth’s rotation in the formation of pressure belts.
Answer:
Solar energy and earth’s rotation plays an important role in the formation of pressure belts. Earth rotation and apparent movement of the sun, which causes an inequality in the amount of heat received by different parts of the earth and its atmosphere. At the equator throughout the year the amount of heat received is intense. Heated air being light, rises, creating low pressure area.

While at the poles, sun rays are slanting and air is so heavy and a high pressure area is created. Rotation of the earth also leads to the formation of various pressure belts on the earth. The pole rotates more slowly than the equator, and the air should be pushed away from the poles towards the equator, where it pile to form a high pressure belt and at the poles it should be a low pressure. But this is just reverse near equatorial region, where the air gets heated and rises, creates low pressure. The poles where cold air sinks, is the high pressure area

Question 3.
Describe how the Coriolis Effect causes the deflection of winds on the basis of the direction of the winds mentioned below,
a. Trade winds
b. Westerlies.
Answer:
Due to the rotation of the earth winds curve as they blow. This curving motion of wind is called coriolis effect. According to this any freely moving bodies get deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. Winds that blows from sub-tropical high pressure belt to equatorial low pressure belt are called trade winds. In Northern Hemisphere trade wind blows from North East direction due to deflection. So it is called North East trade winds.

In southern Hemisphere trade winds blows from South East direction hence it is called South East trade winds. Westerlies winds blow from the sub-tropical high pres sure to sub-polar low pressure. Due to coriolis effect in Northern Hemisphere it is from south west direction and in Southern Hemisphere North west direction. Westerlies are just opposite of trade winds in terms of their direction so westerlies are also called an ti trade winds.

In search of the Source of Wind Orukkam Questions and Answers

Question 1.
Observe and analyse the pictures 2.1,2.3 in the chapter.
List out the factors which influence the atmospheric pressure

Height
Temperature

Answer:
Humidity

Question 2.
Observe and analyse the picture 2.1,2.2,2.3 in the chapter and find out how do the following factors influence the atmosphere pressure
Altitude
Temperature
Humility
Answer:
Altitude — When altitude increases atmospheric pressure decreases.
Temperature — When temperature increases atmospheric pressure decreases.
Humidity — When humidity increases atmospheric pressure decreases.

Question 3.
How does the term ‘High pressure’ differ from the ‘Low pressure’

High pressure	Low pressure
•	•
•	•

Answer:
High Pressure:
Atmospheric pressure is more when com pared to surroundings.
Low Pressure:
Atmospheric pressure is low when compared to surroundings.

Question 4.
Complete the following table based on global pressure belts.

The Global Pressure Belts	Latitudal Postion	Nature	The reason for the formation

The Global Pressure Belts	Latitudal Postion	Nature	The reason for formation
Equatorial Low Pressure Belt	Situated between 5° north and south latitudes	Low pressure, feeble winds	The suns rays falls almost vertically through out the year. Hence air expands due to sun’s heat and rises up on a massive scale.
Subtropical high pressure belts	30° north and south latitudes	High pressure	The hot air ascending from the equatorial low pressure belt cools gradually and subsides at the subtropical zone due to the rotation of the earth.

The Global Pressure Belts	Lattitudal Postion	Nature	The reason for formation
Sub polar low pressure belts	In both sides of 60° latitudes	low pressure	As this zone lies close to the poles, the air isidlder here. Though the cold air remains close to the earth, the air is thrown up due to the rotation of the earth.As a result, low pressure is experienced all along the sub polar region.
Polar High pressure belts	90° latitudes near the poles	High pressure	Air remains chilled under the extreme cold that prevails over the poles and this contributes to the steady high pressure experienced here.

5. List out the factors influencing the speed • Coriolis effect and the direction of winds

Coriolis effect
Pressure Gradient

Answer:
Friction

Question 6.
Write the main features of planetary winds and complete the table.

Answer:

Question 7.
List out the reasons which result in the formation of monsoon.

The apparent movement of the sun

Answer:
Coriolis force, Differences in heat.

Question 8.
Complete the following table by distinguishing between Sea breeze and Land breeze.

Answer:
Land Breeze:

Blows during the night.
Blows from land to sea.

Sea Breeze:

Blows during the daytime.
Blows from sea to land.

Question 9.
Complete the following table by distinguishing between Mountain breeze and Valley breeze.

Answer:
Mountain Breeze:

Blows from mountain towards the valley.
Blows during the night.

Valley Breeze:

Blows from valley towards the mountain.
Blows during the day time.

Question 10.
List out the local winds based on their nature and places where they blow, to complete the following table.

Answer:

Name of the Wind	The places where they blow	Nature
Chinook	Eastern slopes of the Rocky mountains	Dry Wind
Foen	Northern slopes of alps in europe	Dry Wind
Harmattan	Western Africa	Dry Wind
Loo	Great Northern PI ains of India	Dry Hot Wind
Mango showers	South India	Dry Wind

In search of the Source of Wind Evaluation Questions

Question 1.
Distinguish between
a. Land breeze and Sea breeze
b. Mountain breeze and Valley breeze
Answer:
Land breeze:
As the land cools faster than the sea during the right, it would be high pressure over the land and low pressure over the sea. This results in the movement of air from the land to sea. This is the Land Breeze.

Sea Breeze:
Land heats up and cools down quickly than water that leads to the formation of low pressure over the land. So cooler air starts to blow from the sea. This is known as Sea Breeze.

Mountain Breeze:
During night, the air in the mountainous regions cools due to the intense cold conditions in that region. As cool air is denser, it blows towards the valley. This is known as Mountain Breeze.

Valley Breeze:
During the day time, the air in the valley gets heated up more than the air on the mountain tops. As a result the wind blows up slope from the valley. This is known as Vally Breeeze

Question 2.
The trade winds blow from North East direction and from south east direction substantiate.
Answer:
It is due to the coriolis effect that the direction of trade winds is from north east in northern hemisphere and southeast in the southern hemisphere.Otherwise it will be from exact north and south. Freely moving bodies get deflected to the right in the northern hemisphere and to the left in the southern hemisphere due to a force generated as a result of earth’s rotation.

Question 3.
Find out how do the ‘Coriolis effect’ influence the direction of winds.
Answer:
Trade Winds are those which blow from sub tropical high pressure belt to equtorial law pressure belt. Due to the Coriolis effect trade winds blow from north east direction in the northern hemisphere and from the southeast direction in the southern hemisphere Westerlies blow from the subtropical high pressure belts towards the sub polar low pressure belts. It is due to the Coriolis effect that the westerlies blow in the south west direction in the northern hemisphere and in the north west direction in the southern hemisphere.

Question 4.
Which local wind is known as ‘snow eater’ why is it called so?
Answer:
Chinook.The red indian word ‘Chinook’ means snow eater. It causes the melting of snow

Question 5.
The speed of the wind is high over plains and oceans. How do you interpret this statement
Answer:
Since the friction is less over plains and oceans the speed of wind will be high in such places. However places with difficult terrain and dense forest cover will have less speed of wind.

In search of the Source of Wind SCERT Questions and Answers

Question 1.
Observe the following diagrams and find answers to the following Questions.

which diagram represents the low pressure region? Substantiate your answer.
What is the name by which the smooth curved lines in the diagrams are known? What does it indicate?

Answer:
Figure B represents the low pressure region

The value of isobars decreases towards the center.
Isobars
Imaginary lines joining places having equal atmospheric pressure.

Question 2.
Distinguish between
a. Land breeze and Sea breeze
b. Mountain breeze and Valley breeze
Answer:

Characteristic features of land and sea breezes
Characteristic features of mountain and valley breezes

Question 3.
Which are the pressure belts on either side of subtropical high pressure belts?
Write notes on the winds formed from this pressure belt in the northern hemisphere. Which among these winds is most influenced by the Coriolis force? Why?
Answer:

Sub polar low pressure belt and equatorial low pressure belt.
Features of westerlies and north east trade winds.
Westerlies are most influenced by the Coriolis force.
Coriolis force increases while advancing from the equator.

Question 4.
Rearrange the table on the basis of the planetary winds blowing in between different pressure belts.
1. Between the sub-tropical high pressure belt and the sub polar low pressure belt. – Trade winds
2. Between the polar high pressure belt and the sub polar low pressure belts – Westerlies
3. Between the sub-tropical high pressure belts and the equatorial low pressure be Its – Polar winds
Answer:

Westerlies
Polar winds
Trade winds

Question 5.
Read the following information’s.
• The atmospheric pressure at A is 740 mb and it is 730 mb at a place 10 km away from A.
• Atmospheric pressure at B is 740 mb and it is 730 mb at a place 5 km away from B Which among these places experience stronger winds? Why?
Answer:

Place B experience stronger winds
Pressure gradient force is more at B. The isobars are drawn close to each other.

Question 6.
Which among the following winds are called as Roaring forties?
A. Polar winds
B. Monsoon winds
C. Westerlies
D. Trade winds
Answer:
C. Westerlies

Question 7.
Identify the wrong statement among the following.
i. The location of mountains is one among the factors causing the formation of monsoon.
ii. South west trade winds also moves north ward with the equatorial low pressure belt in the northern hemisphere during summer.
iii. South east trade winds moves northward along with the equatorial low pressure belt in the northern hemisphere during summer.
iv. Coriolis effect is one of the factors influencing the formation of monsoon.
a. i, iii and iv are correct, ii is wrong
b. i, ii, and iv are correct, iii is wrong
c. iii and iv are correct, i and ii are wrong
d. i and iv are correct, ii and iii are wrong
Answer:
c is the correct answer

Question 8.
Suppose at a place A the level of mercury in the mercury barometer touches 76cm. What may be the atmospheric pressure then? Calculate the atmospheric pressure experienced at a height of 50 metres over the same.place.
Answer:

Atmospheric pressure 1013.2 mb
Atmos pheric pressure at 50 m height = 1013.2 – (1 mb × 5)= 1008.2 mb

Question 9.
The equatorial low pressure region was a nightmare for the ancient mariners. Why?
Answer:

In ancient times the ocean voyages were – in yachts by making use of winds.
The winds are feeble in the equatorial low pressure region because of massive rising up of air.
This region is also known as Doldrum.
The voyage across this region in yachts was difficult due to the lack of winds.

Question 10.
Explains that the atmospheric pressure is not uniform everywhere.

a. Name the smooth lines in the diagram,
b. Among the places A and B, identify the place experiencing high pressure and the place experiencing low pressure,
c. The sun is in which hemisphere during the period?
Answer:

Isobars
A- Low pressure, B- High pressure
Northern hemisphere

Question 11.
Is the atmospheric pressure the same at all places given below? Write a note based on the factors influencing the atmospheric pressure. .
1. Polar region
2. Central pacific region
3. Ooty
Answer:

Polar region – Low temperature, high pressure
Central pacific region – high temperature, low pressure
Ooty – low temperature, high pressure

Question 12.
Following are a few facts related to two global pressure belts. Identify the pressure belts.
1. Extends to about 5° to 10° north and south of the equator.
2. Located at 30° north and south latitudes on both the hemispheres.
3. Trade winds and Westerlies blows from either side of this belt.
4. Known as Doldrum
Answer:
1 .Equatorial low pressure belt
2. Sub tropical high pressure belt
3. Sub tropical high pressure belt
4. Equatorial low pressure belt

Question 13.
Winds are named according to the place from which they blow. Mention any two winds named accordingly.
Answer:

South west monsoon winds
North east monsoon winds ( name any suitable winds)

Question 14.
Illustrated below are the directions of winds in the northern and southern hemispheres. Identify the figures which are not correct and illustrate them correctly.

Answer:

Figures – b and d are not correct
Correctly illustrate them.

Question 15.
Arrange the items in B and C columns suitable to column A.

A	B	c
Permanent winds	Cyclone	Mousim
Periodic winds	Night	Northern plains
Variable winds	Westerlies	Low pressure over the sea
Local winds	Monsoon winds	Furious fifties
Land breeze	Loo	Low pressure over the sea

Answer:

A	B	c
Permanent winds	Westerlies	Furious fifties
Periodic winds	Monsoon winds	mousim

Variable winds	Cyclones	low pressure center
Local winds	Loo	Northern plains
Land breeze	night	Low pressure over the sea

In search of the Source of Wind Exam Oriented Questions and Answers

Question 1.
Name the hot Local wind which blows from the Rajastan desert.
Answer:
Loo

Question 2.
Choose the correct example for periodic winds given below.
Trade winds, Westerlies, Monsoon winds
Answer:
Monsoon winds

Question 3.
Identify the winds that helped Gama to reach Kerala coast from Malindi?
Answer:
South west monsoon winds.

Question 4.
Westerties are stronger in the southern hemisphere that in the northern hemisphere why?
Answer:
This is due to vast expanse of oceans in the southern hemisphere.

Question 5.
Name the instrument used to measure at-mospheric pressure
Answer:
Barometer (Mercury Barometer, Aneroid Ba¬rometer)

Question 3.
In which unit atmospheric pressure is measured?
Answer:
Hectopascal (hpa), Milibar (mb)

Question 7.
Define the meaning of Atmospheric pressure
Answer:
Pressure exerted by the air is called atmospheric pressure. ,

Question 8.
Atmospheric pressure is not the same in all places on the Earth? Ex plain
Answer:
Attitude, Temperature and humidity are the various factors that effects atmospheric pressure.

Attitude :- When height increases pressure decreases when height increases the amount of air present in atmosphere decreases.

Temperature :- When air gets heated, air starts to expend. As a result air become dense and it rises. This leads to decrease in pressure.

Humidity:- The amount of water vapour present in air is called humidity. The water vapour is less dense than air. So when the amount of water vapour increases atmospheric pressure decreases.

Question 9.
Define high pressure and low pressure? Ans.If the atmospheric pressure of an area is higher than that of the surrounding regions it can be designated as high pressure (H). If the atmospheric of the surrounding region it can be designated as low pressure (L).

Question 10.
What are Isobars? What are the various uses of isobars?
Answer:
isobars are imaginary lines joining places having the same atmospheric pressure. We can easily understand the distribution of the atmospheric pressure of any region by observing the Isobars.

Question 11.
Write a brief note on global pressure belts based on location and factor responsible for the formation.
Answer:
Atmospheric pressure is uniform between certain latitudes. These belts are called Global pressure belts.
Equatorial low pressure belts:

This belts is situated between 5° N and 5°S latitudes.
This is the Zone where the sun rays fall vertically throughout the year.
Hence air expands due to Sun’s heat and riser up on a massive scale

Sub tropical high pressure belts:

This belt lies between latitudes in both Northern and Southern Hemisphere.
The hot air ascending from the equatorial low pressure belts cools gradually and subsides at the Sub tropical Zone due to rotation of the Earth.

Sub polar low pressure belts:

This belt lies bear 60° latitudes in both North and South of the equator.
This zone in close to the pole, the air is colder here.
Though the cold air remains close to theearth, the air is thrown up due to rotation of the Earth. As a result, low pressure is experienced all along the sub polar region.

Polar high pressure belts:

This belt lies 90° latitudes in both the hemispheres.
This zone experience severe cold throughout the year.

Question 12.
What are the factors that contribute to the formation of different pressure belts.
Answer:
Variations in the amount of solar energy received. The rotation of the Earth.

Question 13.
How are the winds formed?
Answer:
Pressure differences lead to the formation of winds. Winds blow from high pressure regions to low pressure in a horizontal manner. This is called wind.

Question 14.
What is the main faction behind the name given to a particular wind?
Answer:
Winds are named on the basis of the direction from which they blow. For example, South wind the wind blowing from South.

Question 15.
The peculiarities of the source regions influence the nature of wind. How?
Answer:
Winds blowing from the sea will be saturated with moisture whereas, the moisture content will be less in winds blowing from drier regions.

Question 16.
Write some factors that determines velocity and direction of wind?
Answer:
Pressure gradient, Force coriolis, Force friction.

Question 17.
What is pressure gradient force?
Answer:
The pressure gradient is said to be sleeper when the pressure difference is more. This can be understand by the pattern of isobar in two different situations. If the isobar are distributed away from each other the pressure gradient will be less. So the speed of wind is feeble.

Question 18.
What is meant by Coriolis force?
Answer:
Freely moving bodies get deflated to the right in the Northern Hemisphere and to the left in the Southern hemisphere due to the force generated as a result of Earth’s rotation. This is known as Coriolis force.

Question 19.
Who introduced Ferrels’sLaw? Explain the Law?
Answer:
Admiral Ferrel introduced this law, an American Scientist. According to this Ferrel’s law winds right and those in the Southern hemisphere deflect towards their left due to the Coriolis effect.

Question 20.
Two different pictures are given be low under two situations. In which of these situations do winds blow smoothly? Why?
Answer:
The speed of wind will be high over ocean surfaces and level lands as the friction is less. On the other hand, the friction being more along difficult terrains and places with dense forest cover, the speed of wind will be less in those places.

Question 21.
Write a short note on planetary winds?
Answer:
The winds developed between the global pressure belts can be generally called as pla-netary. The different planetary winds are listed below:

Trade winds
Westerlies
Polar easterlies

Trade winds : The winds that blow from sub tropical high pressure belt to equatorial low pressure belt is called Trade winds.

Westerlies: The winds that blow from Sub- tropical high pressure belt to sub-polar low pressure belt is called Westerlies.

Polar easterlies: The winds that below from polar high pressure to sub-polar low pressure is called Polax easterlies.

Question 22.
What is Inter Tropical Convergence Zone (TTCZ)?
Answer:
The zone where the trade winds from both the hemispheres converge is known as the Inter Tropical Convergence Zone.

Question 23.
The ancient mariners had given different names to the rough westerlies in the southern hemisphere what are those names? Why it is known is different names?
Answer:
Roaring Forties (along 40° latitude), Furious Fifties (along 50° latitudes) and shrieking sixties (60° latitudes).

Question 24.
Why the polar winds are called polar Easter lies?
Answer:
These winds blow from the east in both the hemispheres due to the coriolis force. Hence these are known as polar easterlies.

Question 25.
Winds that change direction is accordance with season. Explain.
Answer:
Monsoon is the seasonal reversal of wind in a year it changes their direction according to the season. There are many factors responsible for the formation of the monsoon winds. Some of these are:

The apparent movement of the sun
Coriolis force
Differences in heating

Sun’s rays fall vertically to the north of the equator during certain months due to the tilt of the Earth’s axis. This leads to an increase in temperature along the region through which topic of cancer passes. The pressure belts also shifts slightly northwards in accordance with this. The south east trade winds also cross the equator and moves towards the north- wards during the summer in the northern hemisphere. As the trade winds cross the equator they get deflected and transform into south west moon winds under the influence of the coriolis effect. As a result of the formation of high pressure zones over the Asian land mass during winder and low pressure Zones over the Indian Ocean, the north-east trade winds get strengthened. These are the north east monsoon winds. In a year wind deflects their direction twice.

Question 26.
Explain the formation of valley breeze and mountain breeze?
Answer:
During the day time air in the valley gets heated up more than the air on the mountain tops. As a result, the wind blows up shope from the valley. This is known as Valley Breeze. But during right the air in the mountain ous regions cools due to the intense cold conditions in that region. As cool air is demer, it blows towards the valley. This is known as Mountains Breeze.

Question 27.
What are the different types of local winds blows in different parts? Explain?
Answer:
Local winds are winds whose effects are limited to a comparatively it is formed as a result of local pressure differences. Such winds exist in different parts of the world. Loo, Mango Showers and Kalbaisathi are the local winds experienced in India. Chinook, Harmattan and Foehn are some of the local winds in other parts of the world.

Question 28.
What is Chinook? Write a note on features of Chinook.
Answer:
Chinook is a local wind that blows down the eastern slope of the Rocky mountains in North America. As a result of these winds, the snow along the eastern slopes of the Rocks melts. This wind reduces the severity of the cold, it is helpful for the wheat cultivation in the Canadian lowlands.

Question 29.
In which region the wind Foehn blows? What is the main feature of this wind?
Answer:
Foehn is the wind that blows towards the southern valleys of the Alps. As the air heats up due to pressure from the descend, it helps in reducing the severity of cold in that’ region.

Question 30.
In which region the wind Harmattan blows? What are the characteristics of this wind?
Answer:
Harmattan is a day wind which blows from the Sahara desert towards the West Africa.On of the arrival of these winds, the humied and sultry conditions of west Africa is improved significantly. Hence people call these winds as doctor Harmattan.

Question 31.
Name the different types of local winds blow¬ing in India. Write a short note on vari- ous local winds blowing in India?
Answer:
Loo:

Not wind blowing in the North Indian plain.
Hot wind blows is hot dry season.
It increases the summer temperature.
It is experienced in the afternoon.

Mango Showers:

It blows in South India during hot season.
It acquires its name owing to the fall of ripe mangoes on its arrival.

Question 32.
What does thid picture indicate ? Analyse the picyure and prepare a note.

Answer:
The picture indicates Coriolis Force. Freely moving bodies get deflected to the right in the northern hemisphere and to the left in the southern hemisphere due to a force generated as a result of earth’s rotation. This is known as the Coriolis Force. This force increases as it moves towards the poles from the Equator. Admiral Ferrell found out that the winds in the northern hemisphere deflect towards their right and those in the southern hemisphere deflect towards their left due to the Coriolis effect. The law put forward by him on the basis of this known as Ferrell’s Law.

Question 33.
There are different types of winds on the earth’s surface. Complete the following flow.

Answer: