KCET2011PhysicsRay Optics
The time required for the light to pass through a glass slab (refractive index =1.5 ) of thickness 4 ~mm is ( c=3 10⁸ ~ms ⁻¹ , speed of light in free space)
Options
- A10⁻¹¹ ~s
- B2 10⁻¹¹ ~s
- C2 10¹¹ ~s
- D2 10⁻⁵ ~s
Correct answer
B. 2 10⁻¹¹ ~s
Step-by-step solution
We know, gathered n_ a c_ a =n_ g c_ g n_ g n_ a = c_ a c_ g 3 2 = 3 10⁸ c_ g c_ g =2 10⁸ gathered We have, Time = Distance Speed t= 4 10⁻³ 2 10⁸ or t=2 10⁻¹¹ ~s