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A point source of light is placed at the...

A point source of light is placed at the bottom of a vessel which is filled with water of refractive index `mu` to a height h. If a floating opaque disc has to be placed exactly above it so that the source is invisible from above, the radius of the disc should be-

A

`(h)/(sqrt(mu-1))`

B

`(h)/(sqrt(mu^(2)-1))`

C

`(h)/(mu^(2)-1)`

D

`(muh)/(sqrt(mu^(2)-1))`

Text Solution

Verified by Experts

The correct Answer is:
B
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