everyday science MCQ #50892

On a clear day the sky appears blue, but near the horizon at sunset it appears red or orange. What phenomenon is responsible for the blue colour of the daytime sky?

everyday science MCQ #50892

  1. Question 1

    Q1. On a clear day the sky appears blue, but near the horizon at sunset it appears red or orange. What phenomenon is responsible for the blue colour of the daytime sky?

    • A) Reflection of blue ocean water by the atmosphere
    • B) Absorption of all wavelengths except blue by ozone molecules
    • C) Refraction of sunlight at the boundary between space and atmosphere
    • D) Rayleigh scattering, in which short-wavelength blue light is scattered far more than longer wavelengths

    Answer: Rayleigh scattering, in which short-wavelength blue light is scattered far more than longer wavelengths

    Explanation: Rayleigh scattering describes how light interacts with particles much smaller than its wavelength: the scattering intensity is proportional to the inverse fourth power of wavelength, so short-wavelength blue light scatters roughly ten times more than long-wavelength red light in all directions across the sky.