Q. Light travels through a glass plate of thickness $t$ and having refractive index $n$. If $c$ is the velocity of light in vacuum, the time taken by the light to travel this thickness of glass is
A) $\frac{t}{nc}$
B) $tnc$
C) $\frac{nt}{c}$
D) $\frac{tc}{n}$
Explanation
(c) $Time\ = \frac{distance}{speed} = \frac{t}{c/n} = \frac{nt}{c}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.