NCERT Solutions for Class 7 Geography Chapter 4 - Air
In CBSE Class 7, Geography is the easiest and one of the most scoring subjects and is given higher emphasis in Social Science. TopperLearning provides a comprehensive set of study material which will help you to clear your Geography examination with ease. In our CBSE Class 7 study material for Geography, you will find video lessons, revision notes, question banks and sample papers which will help you to get more marks in your examination.
CBSE Class 7 study materials for Geography are written by our subject experts who have experience in teaching the CBSE syllabus. To make study effective, we have ‘Ask the Expert’ section where all your doubts will be solved by our subject experts. For better understanding of the subject, you can refer to our solved papers and textbook solutions such as NCERT textbook solutions which are available online and free of cost. Our objective of providing the study materials is that you get to score well in the examination.
Chapter 4 - Air Exercise 27
(i) Earth is enveloped by a blanket of air. This envelopment/blanket is called ‘atmosphere’.
(ii) Oxygen and nitrogen constitute the bulk of the atmosphere.
(iii) Carbon dioxide creates the greenhouse effect in the atmosphere.
(iv)Weather is the collection of short-term changes in the atmosphere of the Earth. It is, in essence, the hour-to-hour, day-to-day condition of the atmosphere.
(v) Convectional rainfall, orographic rainfall and cyclonic rainfall are the three types of rainfall.
(vi) Air pressure is the pressure exerted by the weight of the air on the surface of the Earth.
(i) – (c) Ozone
(ii) – (a) Troposphere
(iii) – (b) Stratosphere
(iv) – (b) Decreases
(v) – (b) Rain
(i) – (c) Permanent wind
(ii) – (d) Local wind
(iii) – (a) Seasonal wind
(iv) – (b) Horizontal movement of air
(i) Humidity is the amount of moisture or water vapour present in air at any particular point of time. On a humid day, the level of water vapour in the air is more and as the air gets warmer, this level too increases. As a result, wet clothes take longer time to dry on a humid day.
(ii) Insolation is in fact the incoming solar radiations that are intercepted by the Earth. There is a tilt in the axis of the Earth. As a result of this tilt, the sunlight, and by extension, the incoming radiations, cover a larger area at the Equator than at the Poles.
Key Features of Study Material for CBSE Class 7 Geography:
- Most effective study materials
- Prepared by subject experts
- Designed according to the latest CBSE syllabus
- Helpful when doing homework
- Ask the expert facility available
- Ideal for quick revision
- Significantly improve your scores
Kindly Sign up for a personalised experience
- Ask Study Doubts
- Sample Papers
- Past Year Papers
- Textbook Solutions
Verify mobile number
Enter the OTP sent to your number