NCERT Solutions for Class 7 Science Winds, Storms and Cyclones [Old Book]

NCERT
SOLUTIONS
CLASS - 7TH

aglase .co

Book : Science Ncert Solutions | Chapter-8 Science

Class : 7th
Subject : Science
Chapter : 8
Chapter Name : Winds, Storms And Cyclones

Q1 Fill the missing word in the blank spaces in the following statements:
(a) Wind is__________air.
(b) Winds are generated due to__________heating on the earth.
(c) Near the earth’s surface __________air rises up whereas ___________ air comes down.
(d) Air moves from a region of __________ pressure to a region of__________pressure.

Answer. (a) Wind is moving air.
(b) Winds are generated due to uneven heating on the earth.
(c) Near the earth's surface warm air rises up whereas cold air comes down.
(d) Air moves from a region of high pressure to a region of low pressure.

Q2 Suggest two methods to nd out wind direction at a given place.

Answer. The following are the two methods to nd out the direction of wind.
(i) While ying a kite, air exerts pressure on the kite due to which the kite ies. The direction
in which the kite ies is the direction of blowing of wind.
(ii) While riding a bicycle, the direction in which it is dif cult to ride is opposite to the
direction of the blowing wind.
Therefore, while ying a kite or riding a bicycle, the wind direction at a given place can be
determined.

Q3 State two experiences that made you think that air exerts pressure (other than those given
in the text).

Answer. We have experienced that when we blow a balloon, the balloon becomes tight. If we
try to ll more air, then the balloon will burst after an extent. This happens because air exerts
pressure.
We have also experienced the movement of fringes of windows and doors of our houses when
wind blows in a high speed. This also happens because air exerts pressure.

Page 1 of 3 Aglasem Schools

Book : Science Ncert Solutions | Chapter-8 Science

Q4 You want to buy a house. Would you like to buy a house having windows but no
ventilators? Explain your answer.

Answer. A house having windows but no ventilators should not be bought. This is because
warm air is lighter than cold air and therefore, it goes up. This warm air can go outside the
house mostly through ventilators. If there are no ventilators, then the warm air cannot go
outside easily.

Q5 Explain why holes are made in hanging banners and hoardings.

Answer. Air exerts pressure. Wind blowing in high speed may break or displace many things. If
holes are made in hanging banners and hoardings, then air can pass through these holes,
which reduces the air pressure exerted on the banners and hoardings. That is why holes are
made in hanging banners and hoardings.

Q6 How will you help your neighbours in case cyclone approaches your village/town?

Answer. In case cyclone approaches, the neighbours should be helped in the following ways.
(i) By helping in moving to cyclone shelters and other safer places. .
(ii) By asking them to take necessary steps to shift animals, vehicles and household goods to
safer places.
(iii) By calling the emergency services such as police, re brigade and medical centres when
required.

Q7 What planning is required in advance to deal with the situation created by a cyclone?

Answer. The following planning is required to deal with the situation created by a cyclone.
(i) Facilities for cyclone prediction and forecasting which can give cyclone warning in advance.
(ii) Quick information and communication linkages so that information can be spread quickly.
(iii) Construction of cyclone shelters and arrangement for moving people to safer places for
safety during cyclone.

Q8 Which of the following places is unlikely to be affected by a cyclone?
(i) Chennai
(ii) Mangaluru (Mangalore)
(iii) Amritsar
(iv) Puri

Page 2 of 3 Aglasem Schools

Book : Science Ncert Solutions | Chapter-8 Science

Answer. (iii) Amritsar

Q9 Which of the statements given below is correct?
(i) In winter the winds ow from the land to the ocean.
(ii) In summer the winds ow from the land towards the ocean.
(iii) A cyclone is formed by a very high-pressure system with very high-speed winds revolving
around it.
(iv) The coastline of India is not vulnerable to cyclones.

Answer. (i) Correct
In winter the winds ow from the land to the ocean. This is called land breeze.
(ii) Not Correct
In summer the winds ow from the ocean towards the land. This is called sea breeze.
(iii) Not Correct
A cyclone is formed by a very low-pressure system with very high-speed winds revolving
around it. The low-pressure region is called the eye of the cyclone.
(iv) Not Correct
The coastline of India is very vulnerable to cyclones.

Page : 93 , Block Name : Exercise

Page 3 of 3 Aglasem Schools