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A point source of light is placed at a d...

A point source of light is placed at a distance `h`below the surface of a large deep lake.What is the percentage of light energy that escapes directly form the water surface if `mu`of the water=`4//3`?(neglet partial reflection)

A

`50%`

B

`25%`

C

`20%`

D

`17%`

Text Solution

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The correct Answer is:
D
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