A ray of light strikes a cubical slab surrounded by air as shown in the figure. Then the geometrical path length traversed by the light in the slab will be:

Options

A. `2sqrt(3)`m
B. 2m
C. 6m
D. `((sqrt(3))/(2) + (3)/(2))`m

Answer

C

Explanation

Critical angle `(3)/(2)` sin c =1 , sin c = `(2)/(3)`
Geometrical path length travelled by the light in the slab will be = `2+1+2 +1 = 6`m