Question

A light ray is incident on the horizontal surface of a transparent tank of water at an angle of 50^o .

a) Find the refraction angle in the water,

b) what is the speed of light in water,

c) what is the critical angle for total internal reflection for ray going from water back into the air.

d) If an object at the bottom of the tank appears 50 cm deep, what is the true depth?  

Answer 1

ni or 12 Refractive inden of water (42) = 1.33 Incident angle (0) 50° Refractive index of air (ni) 1. a) If Or in the refraction angle in ni sinoi water then = n₂ sinar - sinor = sinti sin 50 12 1.33 Ora 35.17 ° b) Refractive indese : speed of light is free space speed of light in the medium. Heneo speed of ligue in water 8 most 3x10 m/s 2.25x109 mis 2 c) For total it de critical angle Oc internal reflection, or 90°. then. mesinde a na sin or sind a hosom ixsin goo 1.33 Oy ni 2 48.75° d) Appernt depth = 50 cm True depth Apparent depth Tove depth 50 X 1.33 166-5 cm