Optics Question 185
Question: A beam of natural light falls on a system of 6 polaroids, which are arranged in succession such that each polaroid is turned through 30° with respect to the preceding one. The percentage of incident intensity that passes through the system will be
Options:
A) 100%
B) 50%
C) 30%
D) 12%
Show Answer
Answer:
Correct Answer: D
Solution:
If I is the final intensity and I0 is the initial intensity then
$ I=\frac{I _{0}}{2}{{({{\cos }^{2}}30{}^\circ )}^{5}} $
or $ \frac{I}{I _{0}}=\frac{1}{2}\times {{( \frac{\sqrt{3}}{2} )}^{10}}=0.12 $
BETA
