Optics Question 752
Question: What is the time taken (in seconds) to cross a glass of thickness 4 mm and $ \mu $ = 3 by light
[BHU 1998; Pb. PMT 1999, 2001; MH CET 2000; MP PET 2001]
Options:
A) $ 4\times {{10}^{-11}} $
B) $ 2\times {{10}^{-11}} $
C) $ 16\times {{10}^{-11}} $
D) $ 8\times {{10}^{-10}} $
Show Answer
Answer:
Correct Answer: A
Solution:
$ t=\frac{\mu x}{c}=\frac{3\times 4\times {{10}^{-3}}}{3\times 10^{8}}=4\times {{10}^{-11}} $ sec