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A fish looking up through the water sees...

A fish looking up through the water sees the outside world, contained in a circular horizon. If the refractive index of water is `4/3` and the fish is 12 cm below the water surface, the radius of this circle (in cm) is .....

A

`36sqrt(7)`

B

`(36)/(sqrt(7))`

C

`36sqrt(5)`

D

`4sqrt(5)`

Text Solution

Verified by Experts

The correct Answer is:
B
Radius of circle
= t tan c = `(t)/(sqrt(mu^(2)-1)) = -(12)/(sqrt((16)/(19) - 1)) = (36)/(sqrt(7))` cm
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  17. A thin convex lens made from crown glass (mu = 3//2) has focal length ...

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