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

Unpolarized light of intensity 32 Wm−2 passes through three polarizers arranged in a way, such that the transmission axis of the last polarizer is crossed with that of the first. If the intensity of emerging light is 3 Wm−2, what is the angle between the axis of first two polarizers?

A
45
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
60
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
30
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
90
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C 30∘ Now, angle between P1 and P3 is 90∘ Let, θ1→ angle between P1 & P2 And, θ2→ angle between P2 & P3 ⇒θ1+θ2=90∘ After passing through 1st polarizer, the intensity becomes half, i.e. I1=I02 Now, intensity coming out of the 2nd polarizer is, I2=I1 cos2θ1 Intensity coming out of the 3rd polarizer is, I3=I2 cos2 θ1 Here, I3=3 I3=I1cos2θ1cos2θ2 ⇒3=16cos2θ1cos2(90−θ1) ⇒3=16cos2θ1sin2θ1 ⇒3=4×4cos2θ,sin2θ1 ⇒3=4(sin2θ1)2 ⇒sin22θ1=34 ⇒sin2θ1=√32 ⇒2θ1=60 ⇒θ1=30∘ Hence, (C) is the correct angle.

Suggest Corrections
0
Join BYJU'S Learning Program
Related Videos
Polarization II
PHYSICS
Watch in App
Explore more
Join BYJU'S Learning Program