Q. What is the time taken (in $seconds$) to cross a glass of thickness $4\ mm$ and $\mu = 3$ by light
A) $4 \times 10^{- 11}$
B) $2 \times 10^{- 11}$
C) $16 \times 10^{- 11}$
D) $8 \times 10^{- 10}$
Explanation
(a) $t = \frac{\mu x}{c} = \frac{3 \times 4 \times 10^{- 3}}{3 \times 10^{8}} = 4 \times 10^{- 11}s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.