Q. Which gas is present in the largest proportion in the Earth’s atmosphere?
A). Oxygen
B). Carbon dioxide
C). Nitrogen
D). Argon
Answer: C). Nitrogen
Explanation: Nitrogen makes up about 78% of the Earth’s atmosphere, the largest proportion.
Q. The percentage of oxygen in the atmosphere is approximately:
A). 21%
B). 78%
C). 0.03%
D). 1%
Answer: A). 21%
Explanation: Oxygen constitutes about 21% of the atmosphere, essential for respiration.
Q. Carbon dioxide is present in the atmosphere in approximately:
A). 21%
B). 0.03%
C). 78%
D). 1%
Answer: B). 0.03% .
Explanation: Carbon dioxide is a trace gas in the atmosphere, present at around 0.03%.
Q. Atmospheric nitrogen can be made usable for plants through:
A). Photosynthesis only
B). Nitrogen fixation by bacteria
C). Respiration
D). Evaporation
Answer: B). Nitrogen fixation by bacteria
Explanation: Nitrogen fixation converts atmospheric nitrogen into compounds like nitrates, which plants can use.
Q. Which of the following is a major greenhouse gas?
A). Nitrogen
B). Oxygen
C). Carbon dioxide
D). Argon
Answer: C). Carbon dioxide
Explanation: Carbon dioxide is a major greenhouse gas that traps heat in the Earth’s atmosphere.
Q. The greenhouse effect is important because it:
A). Cools the Earth’s surface
B). Keeps the Earth warm and suitable for life
C). Prevents earthquakes
D). Produces rain directly
Answer: B). Keeps the Earth warm and suitable for life
Explanation: Greenhouse gases trap heat in the atmosphere, maintaining a temperature suitable for life.
Q. Excess greenhouse gases in the atmosphere lead to:
A). Global warming
B). Ice age
C). Earthquakes
D). Ozone layer formation
Answer: A). Global warming
Explanation: Too much CO₂, methane, and other greenhouse gases increase Earth’s temperature, causing global warming.
Q. Which layer of the atmosphere is closest to the Earth’s surface?
A). Stratosphere
B). Troposphere
C). Mesosphere
D). Thermosphere
Answer: B). Troposphere
Explanation: The troposphere is the lowest layer of the atmosphere where weather occurs.
Q. On which layer of the atmosphere is it generally free from clouds and ideal for flying planes?
A). Troposphere
B). Stratosphere
C). Mesosphere
D). Thermosphere
Answer: B). Stratosphere
Q. Which layer of the atmosphere is characterized by a decrease in temperature with height?
A). Troposphere and Mesosphere
B). Stratosphere only
C). Thermosphere only
D). Exosphere only
Answer: A). Troposphere and Mesosphere
Explanation: Temperature decreases with height in the troposphere and mesosphere, but increases in the stratosphere and thermosphere.
Q. Match the following atmospheric features with the correct layer:
a. Ozone layer 1. Stratosphere
b. Ionosphere 2. Troposphere
c. Weather phenomena 3. Thermosphere
Options:
A). a–1, b–2, c–3
B). a–2, b–1, c–3
C). a–1, b–3, c–2
D). a–3, b–1, c–2
Answer: C). a–1, b–3, c–2
Q. Which is the correct order of the layers of the atmosphere from the Earth’s surface upwards?
A). Troposphere → Stratosphere → Thermosphere → Mesosphere → Exosphere
B). Troposphere → Mesosphere → Stratosphere → Thermosphere → Exosphere
C). Stratosphere → Troposphere → Mesosphere → Thermosphere → Exosphere
D). Troposphere → Stratosphere → Mesosphere → Thermosphere → Exosphere
Answer: D). Troposphere (-13km)→ Stratosphere (-50km) → Mesosphere (-80km)→ Thermosphere (-400km)→ Exosphere (beyond 400 km)
Q. Match the following terms with their correct descriptions:
a. Weather
b. Climate
c. Temperature
d. Insolation
1. The average atmospheric conditions of a place over a long period
2. The heat energy received from the Sun by the Earth’s surface
3. The day-to-day state of the atmosphere at a place
4. Measure of how hot or cold the air is
Options:
A). a–2, b–4, c–1, d–3
B). a–1, b–3, c–2, d–4
C). a–4, b–2, c–3, d–1
D). a–3, b–1, c–4, d–2
Answer: A). D). a–3, b–1, c–4, d–2
Q. Insolation decreases on moving from:
A). Poles to the Equator
B). Equator to the Poles
C). Tropic of Cancer to the Equator
D). Tropic of Capricorn to the Equator
Answer: B). Equator to the Poles
Explanation: Insolation (incoming solar radiation) is highest at the Equator and decreases toward the Poles due to the curvature of the Earth and the angle of sunlight.
Q. Air pressure is caused by:
A). Weight of the air above a point on Earth’s surface
B). Movement of water in oceans
C). Rotation of the Earth
D). Evaporation of water
Answer: A). Weight of the air above a point on Earth’s surface
Explanation: Air exerts pressure due to the weight of the air column above a given point.
Q. Air pressure decreases with:
A). Increase in altitude
B). Decrease in altitude
C). Increase in temperature only
D). Decrease in temperature only
Answer: A). Increase in altitude
Explanation: The air pressure is maximum at sea level.
Q. Match the following types of air pressure with their correct characteristics:
a. Low Air Pressure
b. High Air Pressure
1. Low temperature with clear and sunny skies
2. High temperature with cloudy skies and wet weather
Options:
A). a–2, b–1
B). a–1, b–2
Answer: A). a–2, b–1
Q. The movement of air from high-pressure areas to low-pressure areas is called:
A). Convection
B). Wind
C). Evaporation
D). Precipitation
Answer: B). Wind
Explanation: Wind is the horizontal movement of air from regions of high pressure to regions of low pressure caused by differences in air pressure.
Q. Match the following types of winds with their examples:
a. Permanent Wind 1. Trade winds, Westerlies and Easterlies
b. Seasonal Wind 2. Monsoon winds
c. Local Wind 3. Loo,Land breeze and Sea breeze
Options:
A). a–1, b–2, c–3
B). a–2, b–1, c–3
C). a–3, b–2, c–1
D). a–1, b–3, c–2
Answer: A). a–1, b–2, c–3
Q. Humidity refers to:
A). The amount of water vapour present in the air
B). The temperature of the air
C). The pressure of the air
D). The wind speed
Answer: A). The amount of water vapour present in the air
Explanation: Humidity measures how much water vapour is present in the atmosphere.
Q. On a humid day, which of the following is likely to occur?
A). Rapid evaporation
B). Sweat from our body does not evaporate easily
C). Clear and dry air
D). Clothes takes less time to dry
Answer: B). Sweat from our body does not evaporate easily
Explanation: High humidity slows down evaporation of sweat, reducing the body’s ability to cool itself.
Q. Why do jet planes flying at high altitudes leave a white trail behind them?
A). Due to smoke from the engines
B). Due to moisture from their engines condenses
C). Due to reflection of sunlight
D). Due to wind currents
Answer: B). Due to moisture from their engines condenses
Q. Consider the following statements:
1. Convectional rainfall is common in tropical regions in the afternoon.
2. Orographic rainfall occurs on the leeward side of mountains.
3. Cyclonic rainfall is associated with storms and cyclones.
Which of the statements given above is/are correct?
A). 1 and 3 only
B). 1 and 2 only
C). 2 and 3 only
D). 1, 2, and 3
Answer: A). A). 1 and 3 only
Explanation: Orographic rainfall occurs on the Windward side of mountains
Q. Which of the following gases protects us from harmful sun rays?
a) Carbon dioxide
b) Nitrogen
c) Ozone
Answer: c) Ozone
Q. The most important layer of the atmosphere is
a) Troposphere
b) Thermosphere
c) Mesosphere
Answer: a) Troposphere
Q. Which of the following layers of the atmosphere is free from clouds?
a) Troposphere
b) Stratosphere
c) Mesosphere
Answer: b) Stratosphere
Q. As we go up the layers of the atmosphere, the pressure
a) Increases
b) Decreases
c) Remains the same
Answer: b) Decreases
Q. When precipitation comes down to the earth in the liquid form, it is called
a) Cloud
b) Rain
c) Snow
Answer: b) Rain