Question

Critical angle for glass medium of refractive index 1.5 is ________
a) 35° b) 42° c) 60° d) 90°

Answer 1

Answer:

42

Explanation:

ic=sin^-1(1/1.5)=42

Answer 2

Answer:

OPTION 'B'

Critical angle =42degrees

Explanation:

Given,

refractive index (n) =1.5

Critical angle (c) =?

To find critical angle we have the formula,

sinc=1/n

sin c =1/1.5

c=42 degrees

Option 'b' is the correct answer.