Course Content
Class 7th Science
Class 7th Math
Online Class For 7th Standard Students (CBSE)
About Lesson

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

  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.


  1.  moving
  2.  uneven
  3.  hot, cool
  4.  high, low

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

  1.  By watching the direction of movement of a dry leaf released in the air.
  2.  By using wind-vanes which helps us to know the accurate wind direction.

Question 3.
State two experiences that made you think that air exerts pressure (other than those given the text).

  1. Blowing air in a balloon makes it expand.
  2. Blowing air can move curtains of doors and windows here and there.

Question 4.
You want to buy a house. Would you like to buy a house having windows but no ventilator? Explain your answer.
No, we would not like to buy a house having windows but no ventilators. We know that warm air rises upward and cool air comes downward. So to make a stream of cool and fresh air flow in continuation inside the house through the windows, there must be some ventilators in the upper parts of the walls.

Question 5.
Explain why holes are made in hanging banners and hoardings.
Air exerts pressure. Due to this pressure, banners and hoarding flutter and tom when the wind is blowing fast. Holes are made in banners and hoardings so that wind passes through the holes and they do not become loose and fall down.

Question 6.
How will you help your neighbours in case a cyclone approaches your village/town?
We will cooperate and help our neighbours, by:
(i) making necessary arrangements to shift the essential household goods, domestic animals and vehicles, etc., to safer places.
(ii) not pressurizing the rescue force by making undue demands.
(iii) asking them:

  • avoid driving on roads with standing water as floods may have damaged the roads.
  • do not drink water that could be contaminated.
  • do not touch wet switches and fallen powerlines.
  • do not go out just for the sake of fun.

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

  1.  Setting up cyclone warning system.
  2.  Construction of cyclone shelters in the cyclone-prone areas.
  3.  Keeping storage of food and water in the cyclone-prone areas.
  4.  Setting up a first-aid facility.

Question 8.
Which one of the following places is unlikely to be affected by a cyclone?

  1.  Chennai
  2.  Mangaluru (Mangalore)
  3.  Amritsar
  4.  Puri

3.  Amritsar because it is far away from the coastal area.

Question 9.
Which of the statements given below is correct?

  1. In winter the winds flow from the land to the ocean.
  2.  In summer the winds flow from the land towards the ocean.
  3.  A cyclone is formed by a very high-pressure system with very high-speed winds revolving around it.
  4.  The coastline of India is not vulnerable to cyclones.

1. In winter the winds flow from the land to the ocean.

Join the conversation
Wisdom TechSavvy Academy