2024 · Q87
Which of the following statements regarding insolation is/are correct?
- 1Insolation is predominantly shortwave radiation, with wavelengths in the range of 0.39 micrometre to 0.76 micrometre.
- 2Insolation is evenly distributed across the Earth because of the Earth's curved surface.
Select the correct answer using the code given below.
General KnowledgeGeography
- A1 only
- B2 only
- CBoth 1 and 2
- DNeither 1 nor 2
Explanation
Statement 1 is correct: insolation (incoming solar radiation) is predominantly shortwave radiation, and the visible portion of the spectrum — the bulk of what reaches and warms the Earth — lies in the wavelength range of about 0.39 to 0.76 micrometres. Statement 2 is incorrect: insolation is not evenly distributed; the Earth's curvature, axial tilt and orbit cause the equatorial regions to receive far more insolation than the polar regions. Only statement 1 is correct, so the answer is (A). (Cross-checked with Testbook's CDS-I 2024 solutions.)