Why is it difficult to see through fog?

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Submitted by examrobotsa on

Q: 80 (CDS-II/2007)
Why is it difficult to see through fog?

question_subject: 

Science

question_exam: 

CDS-II

stats: 

0,23,4,3,23,1,0

keywords: 

{'fog droplets': [0, 0, 1, 0], 'fog': [0, 0, 2, 0], 'refractive index': [0, 1, 1, 5], 'total internal reflection': [0, 1, 2, 1], 'light': [16, 4, 34, 62], 'rays': [0, 0, 1, 0]}

The correct answer is option 2: Rays of light are scattered by the fog droplets.

When light passes through fog, it encounters numerous tiny water droplets suspended in the air. These droplets are larger than the wavelength of visible light, causing the light to scatter in different directions. This scattering of light by the fog droplets disrupts the normal path of the light rays and diffuses the light in all directions.

As a result, the scattered light does not reach our eyes in a direct and focused manner, making it difficult to see through the fog. The scattered light creates a hazy and blurry effect, reducing visibility.

Options 1, 3, and 4 are incorrect explanations for why it is difficult to see through fog. Total internal reflection occurs when light passes from a medium with a higher refractive index to a medium with a lower refractive index, which is not applicable in this case. Fog droplets typically do not absorb light significantly, nor does the refractive index of fog necessarily have to be extremely high to cause reduced visibility.