Answer – Clouds appear white due to Mie scattering of sunlight when it falls on the water droplets or ice crystals present within the clouds.
Explanation:
The color of a cloud is primarily influenced by the type of light it receives. The sun emits white light that encompasses all colors within the visible spectrum. In contrast to Rayleigh scattering, where the light waves surpass the size of gas molecules in the atmosphere, the water droplets constituting a cloud have dimensions comparable to the wavelength of sunlight. When both the droplets and light waves share similar sizes, Mie scattering occurs. This scattering lacks the capacity to distinguish between individual wavelength colors, resulting in an equal scattering of all color wavelengths. The human perception of this uniformly scattered light is that of a white appearance. Therefore, a cloud appears white when viewed from the earth.
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Nevertheless, clouds may not consistently display a white hue. The presence of haze and dust in the atmosphere can lead to clouds taking on yellow, orange, or red tones. When clouds become denser, the sunlight passing through them may decrease or be obstructed, resulting in a grayish appearance. In the absence of direct sunlight, clouds might reflect the color of the sky, presenting a bluish tint.
