NCERT Solutions Class 7 Science
The NCERT Solutions in English Language for Class 7 Science Chapter – 8 (Winds, Storms and Cyclones) has been provided here to help the students in solving the questions from this exercise.
Chapter – 8 (Winds, Storms and Cyclones)
1. 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 air pressure to a region of low air pressure.
2. Suggest two methods to find out wind direction at a given place.
Answer – Methods to finding out the wind direction at a given place are as follows
i. By seeing the direction of dry leaves released in the air.
ii By seeing the direction in which it is difficult to ride the bicycle.
3. 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 fill 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.
4. 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.
5. Explain why holes are made in hanging banners and hoardings.
Answer – Holes in the banners and hoardings helps air to pass through it. Hence, banner can withstand the pressure of the air and remains intact.
6. 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.
- By helping them shift to a safer place.
- By helping them to shift their animals, necessary households and vehicles to a safer place.
- By calling emergency services such as fire station, police and medical centres.
7. 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.
- Facilities for cyclone prediction and forecasting which can give cyclone warning in advance.
- Quick information and communication linkages so that information can be spread quickly.
- Construction of cyclone shelters and arrangement for moving people to safer places for safety during cyclone.
8. Which one of the following places is unlikely to be affected by a cyclone?
(i) Chennai
(ii) Mangaluru (Mangalore)
(iii) Amritsar
(iv) Puri
Answer – (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.
Answer – (i) In winter, the winds flow from the land to the ocean.
