MHT CET202019 Oct 2020Morning ShiftPhysicsRay OpticsActual
A prism having refractive index 2 and refracting angle 30^ has one of the refracting surfaces silvered. The beam of light incident on the other refracting surface will retrace its path, if angle of incidence is [ 6 =0 5 ]
Options
- A⁻¹ ( 3 4 )
- B⁻¹ ( 1 2 )
- C⁻¹ ( 3 2 )
- D⁻¹ ( 1 2 )
Correct answer
D. ⁻¹ ( 1 2 )
Step-by-step solution
(D) A=r₁+r₂ but r₂=0 since is incident normally on the second surface. r ₁= A =30^ n= i r 2 = i 30^ i = 2 30^ = 2 1 2 = 1 2 i = ⁻¹ ( 1 2 )