Radiations coming from the Sun are mostly in the form of
- A.light only.
- B.light and long wavelength infrared.
- C.light and short wavelength infrared.
- D.both short and long wavelength infrared.
Correct answer
Explanation
The correct answer is C, light and short wavelength infrared. The Sun's surface is about 6,000 °C, so most of its energy reaches the Earth as short-wave radiation: visible light and near (short wavelength) infrared, with a small share of ultraviolet. Incoming solar energy is called insolation. Because the Sun is very hot, its radiation peaks at short wavelengths, mainly in the visible band. The atmosphere lets much of this short-wave radiation pass through, and it heats the ground. The warmed Earth, being far cooler, gives the heat back as long-wave (terrestrial) infrared radiation, which carbon dioxide and water vapour absorb; this is why the atmosphere is heated mostly from below. Option A is wrong because a large part of solar energy also comes as infrared, not light alone. Option B is wrong because long wavelength infrared is what the Earth radiates, not what the Sun mainly sends. Option D is wrong because it leaves out visible light, the largest single part of solar radiation, and wrongly adds long-wave infrared. Exam tip: Sun sends short waves (insolation); Earth returns long waves (terrestrial radiation).
Practice Questions
View allD had recently visited Khardung La, Nubra Valley and several Buddhist monasteries. Which one of the following States / UT had she visited ?
- A.Himachal Pradesh
- B.Uttarakhand
- C.Sikkim
- D.Ladakh
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Khardung La, the Nubra Valley and monasteries such as Hemis, Thiksey and Diskit all lie in Ladakh, which became a separate Union Territory in 2019.
Read the full explanation →Consider the following statements about clouds : 1. Two major forms of clouds are stratiform and cumuliform. 2. According to the altitude, clouds are classified as high clouds, middle clouds and low clouds. 3. Stratus, nimbostratus and stratocumulus are types of high clouds. 4. Clouds having nimbo attached to their name produce precipitation. Which of the statements given above are correct ?
- A.1 and 2 only
- B.1, 2 and 4
- C.2 and 4 only
- D.1, 3 and 4
Show answer
Only statement 3 is wrong, because stratus, nimbostratus and stratocumulus are low clouds, not high clouds. Statement 1 is correct: clouds take two basic forms, layered stratiform sheets formed by gentle lifting of air and heaped cumuliform clouds formed by rising convection currents.
Read the full explanation →Which one of the following pairs of City and Lake is not correctly matched ?
- A.Buffalo : Erie
- B.Detroit : Superior
- C.Milwaukee : Michigan
- D.Toronto : Ontario
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Detroit stands on the Detroit River, which links Lake St. Clair to Lake Erie, and is far from Lake Superior.
Read the full explanation →Which of the following statements is/are correct with respect to Time Zone in India ? 1. There is one standard time for the whole country. 2. Andaman and Nicobar Islands and Lakshadweep Islands have different Time Zones. 3. Indian Standard Time (IST) is five and half hours behind GMT. Select the correct answer using the code given below:
- A.1 only
- B.2 only
- C.1 and 2 only
- D.1 and 3 only
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India follows a single standard time, Indian Standard Time, for the whole country, and it is ahead of GMT, not behind it.
Read the full explanation →Which one of the following is not a resultant of the El Nino effect ?
- A.Distortion of equatorial atmospheric circulation
- B.Flow of the South-East Trade Winds towards the Indian Ocean
- C.Irregularities in the evaporation of sea water
- D.Reduction in the amount of planktons which reduces the number of fish in the sea
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During El Nino the trade winds of the Pacific weaken or even reverse, so a steady flow of these winds is not one of its results.
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