NCERT Class 7 Science Eighth Chapter Winds, Storms and Cyclones Exercise Solutions

Winds, Storms and Cyclones

Inside Question and Answers:

What is called wind?

Ans. Moving air is called the wind.

Define thunderstorm?

Ans. The swift movement of the falling water droplets along with the rising air create lightning and sound. It is this event that we call a thunderstorm.

What precautions to be taken while If a storm is accompanied by lightning?

Ans. The Precautions are following –

Do not take shelter under an isolated tree.

If you are in a forest take shelter under a small tree.

Do not lie on the ground.

Do not take shelter under an umbrella with a metallic end.

Do not sit near a window.

Open garages, storage sheds, metal sheds are not safe places to take shelter.

A car or a bus is a safe place to take shelter.

If you are in water, get out and go inside a building.

What is called centre of a cyclone?

Ans. Eye.

What is the factor needed for cyclone?

Ans. Factors like wind speed, wind direction, temperature and humidity contribute to the development of cyclones.

What is the name of cyclones in American continent and in Philippines and Japan?

Ans. Hurricane  in American continent and typhoon in Philippines and Japan.

What precautions to be taken while cyclone?

Ans. Do not drink water that could be contaminated.

Always store drinking water for emergencies.

Do not touch wet switches and fallen power lines.

Do not go out just for the sake of fun.

Do not pressurise the rescue force by making undue demands.

Cooperate and help your neighbours and friends.

1. Fill the missing word in the blank spaces in the following statements:

(a) Wind is——————air.

Ans. (a) moving.

(b) Winds are generated due to——————heating on the earth.

Ans. (b) uneven

(c) Near the earth’s surface __________air rises up whereas ___________ air comes down.

Ans. (c) warm, cooler

(d) Air moves from a region of ——— pressure to a region of——— pressure.

Ans. (d) high, low.

2. Suggest two methods to find out wind direction at a given place.

Ans. I. Wind Vane.

1. Take a palm of dust and loose it, check where the bit of dust were flown.
2. State two experiences that made you think that air exerts pressure (other than those given in the text).

Ans. 3. I. air in the bicycle tube keeps it tight.

1. Crumple a small piece of paper into a ball of size smaller than the mouth of an empty bottle. Hold the empty bottle on its side and place the paper ball just inside its mouth. Now try to blow on the ball to force it into the bottle.
2. You want to buy a house. Would you like to buy a house having windows but no ventilators? Explain your answer.

Ans. No, Because warm air is lighter than cold air so it will always go in upperside. The warm air of house is passed through ventilators. The windows is only for enter fresh air of outsiders.

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

Ans. Holes are made in hanging  banner so that air is passed so easily whoever no the banner will be torn up or loose or fall.

6. How will you help your neighbors in case cyclone approaches your village/town?

Ans. Make necessary arrangements to shift the essential household goods, domestic animals and vehicles, etc. to safer places.

Keep ready the phone numbers of all emergency services like police, fire brigade, and medical centres.

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

Ans. Check Inside Questions and Answers.

8. Which one of the following place is unlikely to be affected by a cyclone.

(i) Chennai

(ii) Mangaluru (Mangalore)

(iii) Amritsar

(iv) Puri

Ans. (iii) Amritsar

9. Which of the statements given below is correct?

(i) In winter the winds flow from the land to the ocean.

(ii) In summer the winds flow 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

Ans. (i) In winter the winds flow from the land to the ocean.