MCQ
One cannot see through fog because ..........?
  • A
    Fog absorbs light
  • B
    Refractive index of fog is unity
  • C
    Light suffers total internal reflection at the droplets in fog
  • D
    Light is scattered by the droplets in fog

Answer

  1. Light is scattered by the droplets in fog

Explanation:

Atoms and molecules in the air, including anything carried in the air like dust or smoke, will scatter light. Water droplets, as they are present in fog, also scatter light.

The light falling on an object and reflected to a viewer can be scattered to heck and back before it gets to the place where it can be 'seen' by an observer.

So the observer just sees a 'whiteout' instead of being able to make out anything beyond a few meters or so.

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