Three identical polaroids P_1, P_2 and P_3 ar | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(C) According to Malus' law,the intensity of light transmitted through a polarizer is $I = I_{in} \cos^2 	heta$,where $	heta$ is the angle between t

Vedclass · Accepted Answer

$\frac{3 I_0}{32}$

Vedclass · Answer

(C) According to Malus' law,the intensity of light transmitted through a polarizer is $I = I_{in} \cos^2 	heta$,where $	heta$ is the angle between the polarization direction of incident light and the pass axis of the polarizer.$1$. When unpolarized light of intensity $I_0$ passes through the first polaroid $P_1$,the intensity of the transmitted light is $I_1 = \frac{I_0}{2}$.$2$. The light from $P_1$ is now polarized at an angle $0^{\circ}$ relative to $P_1$'s axis. $P_2$ is at $60^{\circ}$ to $P_1$. Thus,the intensity after $P_2$ is:$I_2 = I_1 \cos^2(60^{\circ}) = \frac{I_0}{2} 	imes (0.5)^2 = \frac{I_0}{2} 	imes \frac{1}{4} = \frac{I_0}{8}$.$3$. The light from $P_2$ is polarized at $60^{\circ}$ relative to $P_1$. $P_3$ is at $90^{\circ}$ relative to $P_1$. The angle between the polarization of light from $P_2$ and the pass axis of $P_3$ is $	heta = 90^{\circ} - 60^{\circ} = 30^{\circ}$.$4$. The intensity after $P_3$ is:$I_3 = I_2 \cos^2(30^{\circ}) = \frac{I_0}{8} 	imes \left(\frac{\sqrt{3}}{2}ight)^2 = \frac{I_0}{8} 	imes \frac{3}{4} = \frac{3 I_0}{32}$.

Similar Questions

In an experiment,two polaroids are arranged such that the intensity of the polarised light emerged from the second polaroid is $37.5 \%$ of the intensity of the unpolarised light incident on the first polaroid. Then the angle between the axes of the two polaroids is (in $^{\circ}$)

Polarized glass is used for sunglasses because...

Unpolarized light falls on two polarizing sheets placed one after another. What should be the angle between the pass axes of the sheets so that the final transmitted light has one-fourth the intensity of the incident light?

$A$ plane polarized light is incident normally on a tourmaline plate. Its $\vec{E}$ vectors make an angle of $60^{\circ}$ with the optic axis of the plate. Find the percentage difference between initial and final intensities. (in $\%$)

Vedclass Test Series

Exam Paper Generator

Online Exam Module