There is a small source of light at some depth below the surface of water (refractive…
PHYSICS · Single correct · CBSE · Physics · Ray Optics and Optical Instruments · Ray Optics and Optical Instruments
Problem
There is a small source of light at some depth below the surface of water (refractive index =34 ) in a tank of large cross sectional surface area. Neglecting any reflection from the bottom and absorption by water, percentage of light that emerges out of surface is (nearly): [Use the fact that surface area of a spherical cap of height h and radius of curvature r is 2πrh ]
(1) 21%
(2) 34%
(3) 17%
(4) 50%