UPSC Physical Geography – Chapter 13: Humidity, Clouds and Precipitation (22 MCQs)

← Back

UPSC Physical Geography – Chapter 13: Humidity, Clouds and Precipitation (22 MCQs) – 22 questions, subject: Geography. Every question has the correct answer with a one-line explanation; tap "Show Answer". Free practice for TNPSC, UPSC, SSC, Bank and RRB exams – Shanmugam IAS Academy, Coimbatore.

Get daily current affairs & exam alerts – follow us YouTube WhatsApp Channel Telegram Channel Facebook Page Instagram
Share with friends & study groups
Link to this page from your website / blog (HTML code)
1.  

Relative humidity is:

Correct Answer: B [the percentage of moisture in the air compared with its full capacity at that temperature]

Explanation:

Relative humidity compares the moisture actually present with the maximum the air can hold at that temperature, expressed as a percentage.

2.  

The dew point is the temperature at which:

Correct Answer: D [air becomes saturated with water vapour]

Explanation:

At the dew point the air holds all the water vapour it can at that temperature, so it is saturated and condensation begins.

3.  

Frost forms when:

Correct Answer: C [the dew point is at or below freezing]

Explanation:

When the dew point is at or below 0 °C, vapour condenses on cold surfaces directly as ice crystals, which is frost.

4.  

The highest of the basic cloud types, formed at 8,000–12,000 m, are:

Correct Answer: A [cirrus]

Explanation:

Cirrus form at 8,000–12,000 m according to NCERT, the greatest height of the four basic cloud types.

5.  

Thunderstorms are associated with:

Correct Answer: C [cumulonimbus clouds]

Explanation:

Cumulonimbus are towering clouds of vertical development with anvil tops that bring heavy rain, lightning, thunder and sometimes hail.

6.  

Orographic rainfall occurs when:

Correct Answer: A [moist air is forced to rise over a mountain barrier]

Explanation:

When saturated air meets a mountain barrier it is forced up the slope, expands, cools to its dew point and rains on the windward side.

7.  

A rain-shadow area lies on the:

Correct Answer: C [leeward slope of a mountain]

Explanation:

Air descending the leeward slope warms and dries after shedding its moisture on the windward side, so the lee is a rain shadow.

8.  

Hailstones are formed when:

Correct Answer: C [raindrops are carried repeatedly up into freezing levels by strong updrafts]

Explanation:

Strong updrafts in cumulonimbus clouds lift drops repeatedly into freezing levels, adding ice layers until the stones are heavy enough to fall.

9.  

Smog is:

Correct Answer: D [fog mixed with smoke]

Explanation:

Smog is fog mixed with smoke, typical of calm winter weather in polluted urban and industrial areas (Table 13.1).

10.  

Consider the following statements:

1. Warm air can hold more water vapour than cold air.
2. Relative humidity rises when air cools, if its moisture content stays the same.
3. Absolute humidity is expressed as a percentage.

Which of the statements given above is/are correct?

Correct Answer: B [1 and 2 only]

Explanation:

Statements 1 and 2 are correct; statement 3 is wrong because absolute humidity is expressed in grams per cubic metre.

11.  

Assertion (A): Equatorial regions receive convectional rain almost every afternoon.

Reason (R): Intense heating makes the air rise, cool and condense into towering clouds.

Correct Answer: A [Both A and R are true, and R is the correct explanation of A]

Explanation:

Both are true and linked: intense daytime heating makes moist air rise, cool and condense, giving the afternoon convectional showers.

12.  

Nimbus clouds are:

Correct Answer: B [dark grey or black, dense and rain-bearing]

Explanation:

NCERT describes nimbus as black or dark grey, extremely dense, opaque to sunlight and rain-bearing.

13.  

Condensation in free air requires:

Correct Answer: D [cooling of air to its dew point and the presence of hygroscopic nuclei]

Explanation:

Condensation in free air needs both cooling to the dew point and hygroscopic nuclei such as dust, smoke or salt.

14.  

According to NCERT, mist differs from fog in that mist:

Correct Answer: D [contains more moisture than fog]

Explanation:

NCERT states that mist contains more moisture than fog, with a thicker layer of moisture on each nucleus.

15.  

Sleet consists of:

Correct Answer: A [frozen raindrops and refrozen melted snow]

Explanation:

NCERT defines sleet as frozen raindrops and refrozen melted snow-water, formed when a freezing layer lies near the ground.

16.  

Cyclonic (frontal) rainfall occurs when:

Correct Answer: A [warm air is lifted over cold air along a front]

Explanation:

Along a front the lighter warm air is forced to rise over the denser cold air, cools and gives extensive, prolonged rain.

17.  

Arrange the following in chronological order:

1. First International Cloud Atlas
2. Franklin's kite experiment
3. Damini lightning app launched
4. Howard's classification of clouds

Select the correct answer using the code given below:

Correct Answer: C [2-4-1-3]

Explanation:

1752, 1803, 1896, 2020.

18.  

According to NCERT, which one of the following best describes the distribution of rainfall between 45° and 65° N and S of the equator?

Correct Answer: B [It is first received on the western margins of the continents, owing to the westerlies, and decreases eastward]

Explanation:

the westerlies blow from the oceans onto the western coasts, so rain falls there first and decreases eastward.

19.  

Humidity is measured with a:

Correct Answer: D [hygrometer]

Explanation:

A hygrometer measures humidity, the water vapour present in the air.

20.  

The Konkan and Malabar coasts get very heavy rain in the south-west monsoon mainly because:

Correct Answer: D [moist sea winds are forced to rise over the Western Ghats]

Explanation:

orographic rain on the windward slope.

21.  
UPSC Prelims 2019

Why are dewdrops not formed on a cloudy night?

Correct Answer: B [Clouds reflect back the Earth's radiation.]

Explanation:

the clouds send the radiation back, so the ground does not cool to the dew point.

22.  
UPSC Prelims 2013

During a thunderstorm, the thunder in the skies is produced by the

1. Meeting of cumulonimbus clouds in the sky.
2. Lightning that separates the nimbus clouds.
3. Violent upward movement of air and water particles.

Select the correct answer using the code given below:

Correct Answer: D [None of the above produces the thunder]

Explanation:

thunder comes from the sudden expansion of air heated by lightning.

➤ Full notes, maps, tables, a reason for every option and Mains PYQs – U08 · Physical Geography (UPSC book, ₹249): www.shanmugamiasacademy.in/study-materials/upsc-physical-geography

📘 U08 · Physical Geography – UPSC Civil Services (Prelims & Mains)
Here you get the answer with a one-line explanation. 21 chapters · 456 MCQs incl. UPSC Prelims PYQs with a reason for every option · 105 Mains questions + Mains PYQs · maps, tables, revision cards
Get the book – ₹249 ₹499 →
Score: 0 Answered: 0 / 0