1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

# Consider a tank made of glass (refractive index 1.5) with a thick bottom. It is filled with a liquid of refractive index μ. A student finds that, irrespective of what the incident angle i (see figure) is for a beam of light entering the liquid, the light reflected from the liquid glass interface is never completely polarized. For this to happen, the minimum value of μ is:

A
53
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
53
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
35
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
43
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

## The correct option is C 3√5 For any reflected rays not to completely get polarized, ic<ib−−−(1) According to Brewster's law, tanib=1.5μ ⇒sinib=1.5√μ2+(1.5)2 The critical angle between air and the liquid is given by, sinic=1μ From (1), sinic<sinib ⇒1μ<1.5√μ2+(1.5)2 ⇒√μ2+(1.5)2<1.5×μ ⇒μ2+(1.5)2<(μ×1.5)2 ⇒μ>3√5 Therefore, the minimum value of μ should be 3√5 Hence, option (B) is correct.

Suggest Corrections
18
Join BYJU'S Learning Program
Related Videos
Light as Wave
PHYSICS
Watch in App
Explore more
Join BYJU'S Learning Program