A. Fill in the blanks:
1. Wind is ………………. air.
2. Winds are generated due to ……………… heating on the earth.
3. Near the earth’s surface ……………….. air rises up whereas …………….. air comes down.
4. Air moves from a region of ………………….. pressure to a region of …………….. pressure.
5. ………………. winds are called storms.
B. Answer the following questions in short:
1. Suggest two methods to find out wind direction at a given place.
2. State two experiences that made you think that air exerts pressure.
3. You want to buy a house. Would you like to buy a house having windows but no ventilators? Explain your answer.
4. Explain why holes are made in hanging banners and hoardings.
5. How will you help your neighbours in case cyclone approaches your village/town?
6. What planning is required in advance to deal with the situation created by a cyclone?
7. What is air pressure?
8. Why does heated air rise up?
9. Bicycle tubes burst when they are overfilled. Why?
10. When strong/high speed wind blows, an umbrella held upright at times gets up-turned. Explain the reason.
C. Tick (œ“) the correct option:
1. Which one of the following place is unlikely to be affected by a cyclone?
(a) Chennai
(b) Mangaluru (Mangalore)
(c) Amritsar
(d) Puri
2. Which of the statements given below is correct?
(a) In winter the winds flow from the land to the ocean.
(b) In summer the winds flow from the land towards the ocean.
(c) A cyclone is formed by a very high-pressure system with very high-speed winds revolving around it.
(d) The coastline of India is not vulnerable to cyclones.
3. Factors on which atmospheric pressure depends are:
(a) altitude
(b) temperature
(c) water vapour
(d) all of these
4. The speed of which is measured by:
(a) wind vane
(b) anemometer
(c) barometer
(d) hygrometer
