Air Class 7 MCQs | CBSE Geography
Air Class 7 MCQs | CBSE Geography
Class: 7 |
Subject: Social Science |
Section: Geography – Our Environment |
Topic: Air
These Multiple Choice Questions (MCQs) are designed strictly as per the NCERT syllabus, making them ideal for CBSE Class 7 Social Science Examination preparation.
1. The blanket of air surrounding the Earth is called:
Answer: B. Atmosphere
The atmosphere is the layer of gases surrounding Earth. It protects life by providing oxygen, regulating temperature, and blocking harmful solar radiation.
The atmosphere is the layer of gases surrounding Earth. It protects life by providing oxygen, regulating temperature, and blocking harmful solar radiation.
2. Which gas is most abundant in the atmosphere?
Answer: B. Nitrogen
Nitrogen makes up about 78% of the atmosphere. It is essential for plant growth through the nitrogen cycle.
Nitrogen makes up about 78% of the atmosphere. It is essential for plant growth through the nitrogen cycle.
3. Oxygen constitutes approximately:
Answer: B. 21%
Oxygen supports respiration and combustion. Though less abundant than nitrogen, it is vital for life.
Oxygen supports respiration and combustion. Though less abundant than nitrogen, it is vital for life.
4. The layer closest to Earth is:
Answer: C. Troposphere
All weather phenomena like rain, clouds, and storms occur in the troposphere.
All weather phenomena like rain, clouds, and storms occur in the troposphere.
5. Weather changes take place in:
Answer: A. Troposphere
This layer contains most air mass and water vapour, making it the center of weather activity.
This layer contains most air mass and water vapour, making it the center of weather activity.
6. The ozone layer is found in:
Answer: B. Stratosphere
The ozone layer absorbs harmful ultraviolet rays, protecting living beings.
The ozone layer absorbs harmful ultraviolet rays, protecting living beings.
7. Air pressure decreases with:
Answer: A. Height
As altitude increases, air becomes thinner, reducing pressure.
As altitude increases, air becomes thinner, reducing pressure.
8. Moving air is called:
Answer: B. Wind
Wind is caused by differences in air pressure from uneven heating.
Wind is caused by differences in air pressure from uneven heating.
9. Instrument to measure air pressure:
Answer: B. Barometer
Barometers help forecast weather by measuring pressure changes.
Barometers help forecast weather by measuring pressure changes.
10. Instrument to measure wind speed:
Answer: C. Anemometer
Anemometers record wind velocity, important in meteorology.
Anemometers record wind velocity, important in meteorology.
11. Water vapour in air causes:
Answer: B. Humidity
Humidity influences rainfall, cloud formation, and comfort levels.
Humidity influences rainfall, cloud formation, and comfort levels.
12. Clouds are formed by:
Answer: B. Condensation
Water vapour cools and condenses into droplets forming clouds.
Water vapour cools and condenses into droplets forming clouds.
13. Rain, snow, and hail are forms of:
Answer: B. Precipitation
Precipitation occurs when water droplets grow heavy and fall.
Precipitation occurs when water droplets grow heavy and fall.
14. The hottest atmospheric layer is:
Answer: B. Thermosphere
Temperatures rise sharply here due to absorption of solar radiation.
Temperatures rise sharply here due to absorption of solar radiation.
15. The coldest layer is:
Answer: A. Mesosphere
This layer records extremely low temperatures.
This layer records extremely low temperatures.
16. Air contains which life‑supporting gas?
Answer: B. Oxygen
Oxygen is essential for respiration in living organisms.
Oxygen is essential for respiration in living organisms.
17. Global warming is caused mainly by increase in:
Answer: C. Carbon dioxide
CO₂ traps heat, enhancing the greenhouse effect.
CO₂ traps heat, enhancing the greenhouse effect.
18. Local winds are caused by:
Answer: A. Pressure differences
Unequal heating creates pressure variations generating winds.
Unequal heating creates pressure variations generating winds.
19. Monsoon winds bring:
Answer: B. Rainfall
Monsoons are seasonal winds responsible for major rainfall in India.
Monsoons are seasonal winds responsible for major rainfall in India.
20. Which layer protects Earth from meteoroids?
Answer: B. Mesosphere
Meteoroids burn upon entering this layer, protecting Earth.
Meteoroids burn upon entering this layer, protecting Earth.