What phenomenon explains why the sky appears blue?
A
Total internal reflection
B
Reflection
C
Refraction
D
Rayleigh scattering
Correct Answer: Option D — Rayleigh scattering
Explanation:
Rayleigh scattering explains why the sky appears blue: shorter wavelengths of sunlight, like blue and violet, scatter more strongly by gas molecules in the atmosphere than longer wavelengths like red. Since our eyes are more sensitive to blue, the sky appears blue.