MCQ
One cannot see through fog because .......... :
- AFog absorbs light.
- BRefractive index of fog is unity.
- CLight suffers total internal reflection at the droplets in fog.
- DLight is scattered by the droplets in fog.
✓
Answer
- Light is scattered by the droplets in fog.
Explanation:
We cannot see through fog because of scattering.
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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