8. Winds, Storms and Cyclones Science class 7 in English Medium ncert book solutions NCERT Exercise

Exercise 

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) Moving (b) Uneven (c) Hot, cool (d) High, low.

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

Answer:

(i) By watching the direction of movement of a dry leaf released in air.

(ii) By wind watching directuon indicator.

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

Answer:

(i) Blowing air in a ballon makes it expand.                            (ii) Blowing air can move curtainon doors and windows. 

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

Answer:

No. Ventiiars provide a path for warm air to go out of the rooms. Ventilators help in preventing collapase of rooms during high speed winds.

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

Answer:

Holes are made in hanging so that blowing and can pass through the holes without damaging them. Otherwise they would be blown away because of air pressure.

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

Answer:

(i) By watching everyone about the coming danger.

(ii) Searching for shelter.

(iii) Keeping storage of water and food.

(iv)By setting up first aid facility.

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

Answer:

(i) Setting up of a cyclone forecast and warning service.

(ii) construction of cyclone shelters in the cyclone prone areas.

(iii) Making stock of food and water. 

(iv) keeping first aid facility alongwith.

Q8. Which one of the following place is unlikely to be affected by a cyclone.

(i) Chennai   (ii) Mangaluru (Mangalore)  

(iii) Amritsar  (iv) Puri

Answer:

(iii) Amritsar

Q9. 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.

Answer:

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