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A boy observes a piece of stone at the bottom of a river 6.0m deep. If he looks from ...

A boy observes a piece of stone at the bottom of a river 6.0m deep. If he looks from the surface of the river, what is the apparent distance of the stone from him? [Refractive Index of Water = 4/3]
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  • A 8.0m
  • B 5.5m
  • C 5.0m
  • D 4.5m
Correct Answer: Option D
Explanation:
Refractive Index = Real Depth/App. Depth
4/3 = 6/app. depth
App Depth = (3 x 6)/4 = 4.5m

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