Question

A transparent cuboid contains a small air bubble, which apparent distance is 1.5 cm when seen through one face and 3.5 cm when seen through other face. If refractive index of transparent cuboid is 1.5, then real length of the edge of cube is 

(a) 6 cm 

(b) 5 cm 

(c) 9 cm 

(d) 7.5 cm

Answer 1

Answer is (d) 7.5 cm

⇒ Real depth = 7 5. cm

∴ Real length of the edge of cube = 7 5. cm