The NCERT solutions for class 7 science chapter 8 comprises of a wide range of concepts. These concepts helps the students to comprehend, learn and write them well in their upcoming exams. This is a ready reckoner for the class 7 students. As mentioned earlier, there are a wide range of theories in this chapter. They are –
- Air exerts pressure
- High speed winds are accompanied by reduced air pressure
- Air expands on heating
- Wind currents are generated due to uneven heating on the earth
- Uneven heating between the equator and the poles
- Uneven heating of land and water
- Thunderstorms and cyclones
- How does a thunderstorm becomes a cyclone
- Destruction caused by the cyclones
- Effective safety measures
- Advanced technology has helped
Important Questions for Class 7 Science Chapter 8 NCERT Solutions
Find below the example questions and answers.
Q1. Fill the missing word in the blanks
- _____ air is wind.
- Due to the ___ heating on the earth winds are generated.
- ____air rises up and _____ air comes down near the earth’s surface.
- Air moves from a region of _____ pressure to a region of _____ pressure.
- warm, cooler
- high, low
Q2. Comment on any two methods to find out the wind direction at a given place.
(i) Take a piece of paper, allow it to fall .It will flow in the direction in which wind is blowing.
(ii)A wind-pane can also be used to measure accurate wind direction.
Q3. State any two experiences that made you think that air exerts pressure.
(i) Balloons can be used only when they are filled with air. When balloon is overfilled with air it bursts due to excessive air pressure.
(ii) For stopping trains, compressed air is used in the brake system.
Q4. You want to buy a house. Would you prefer a house having more windows but no ventilators? Explain.
A house which has no ventilators is not safe to live in because there is no air circulation in the house and there wouldn’t be any fresh air coming in. This is because warm air rises up and goes through ventilators and fresh air comes in.
Q5. Explain why holes are made in hanging banners and hoardings.
Pressure banners and hoarding flutters are torn when wind is blown fast. This is because air exerts pressure. Holes are made in banners and hoardings so that wind passes through the holes and they do not become loose and fall down.
Q6. How will you help your neighbors in case of a cyclone approaching your city/town?
(i)Make them aware of cyclone service and warning forecast.
(ii)Giving rapid warnings to the government agencies and all other important places.
(iii)Construction of cyclone shelters in the cyclone prone areas.
(iv)Helping them to shift essential goods, domestic animals etc. to safer places.
Q7. What planning is required in advance to deal with a situation created by a cyclone?
It is important to follow the following measures in order to deal with a cyclone:
(i)By carefully listening to the warnings transmitted on T.V and radio.
(ii)Moving to the safer places.
(iii)keeping an emergency kit ready.
(iv)store food in waterproof bags.
(v)not venturing into the sea.
(vi)keeping all the emergency numbers.
Q8. Which one of the following places is unlikely to be affected by a cyclone?
Q9. Which of the statements given below is correct?
(i) The winds flow from land to ocean during winter.
(ii) The winds flow from land towards ocean during summer.
(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.
(i)The winds flow from the land to the ocean.