A ball is dropped from a height of 20 ~m above the surface of water in a lake. The refractive index of water is 4 3 . A fish inside the lake, in the line of fall of the ball, is looking at the ball. At an instant, when the ball is 12.8 ~m a

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A ball is dropped from a height of 20 ~m above the surface of water in a lake. The refractive index of water is 4 3 . A fish inside the lake, in the line of fall of the ball, is looking at the ball. At an instant, when the ball is 12.8 ~m above the water surface, the fish sees the speed of ball as

Quantrex Academy · Accepted Answer

Correct answer: C. 16 ~ms ⁻¹

v= 2 g h = 2 10 7 =12 ~ms ⁻¹ In this case when eye is inside water, x_ app. = x d x_ app. d t = d x d t or v_ app. = v= 4 3 12=16 ~ms ⁻¹

A ball is dropped from a height of 20 ~m above the surface of water in a lake. The refractive index of water is 4 3 . A fish inside the lake, in the line of fall of the ball, is looking at the ball. At an instant, when the ball is 12.8 ~m above the water surface, the fish sees the speed of ball as

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