What happens when the sunlight travels through the Earth's atmosphere?
A.The blue colour is scattered more compared to the red colour✓ Correct
B.The red colour is scattered more compared to the blue colour
C.Both the blue and the red colours are scattered equally
D.The blue colour is not scattered but the red colour is scattered the most
Explanation
According to Rayleigh's law of scattering, the intensity of scattered light is inversely proportional to the fourth power of the wavelength (I ∝ 1/λ⁴). Blue light has a shorter wavelength (~450 nm) compared to red light (~700 nm), so blue light is scattered approximately 10 times more than red light by the small molecules in the Earth's atmosphere. This is why the sky appears blue during the day. At sunrise and sunset, the blue light is scattered away while the red reaches the observer, making the sun appear reddish.
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