question_answer

A diver looking up through the water sees the outside world contained in a circular horizon. The refractive index of water is\[\frac{4}{3},\] and the diver’s eyes are 15 cm below the surface of water. Then the radius of the circle is:                                             [JEE ONLINE 09-04-2014]

A) \[15\times 3\times \sqrt{5}cm\]

B) \[15\times 3\sqrt{7}cm\]

C) \[\frac{15\times \sqrt{7}}{3}cm\]

D) \[\frac{15\times 3}{\sqrt{7}}cm\]

Correct Answer: D

Solution :

[d] Given,

h = 15 cm

R = ?

or,

or