Two beams,A and B,of plane polarized light wi | vedclass

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

Question

(C) According to Malus's law,the intensity of the emerging beam is given by $I = I_0 \cos^2 	heta$.Let the initial intensity of beam $A$ be $I_A$ and

Vedclass · Accepted Answer

$\frac{1}{3}$

Vedclass · Answer

(C) According to Malus's law,the intensity of the emerging beam is given by $I = I_0 \cos^2 	heta$.Let the initial intensity of beam $A$ be $I_A$ and beam $B$ be $I_B$. When the polaroid is at the position where beam $A$ has maximum intensity,the angle between the transmission axis of the polaroid and the plane of polarization of beam $A$ is $0^{\circ}$,and for beam $B$ it is $90^{\circ}$.After rotating the polaroid by $30^{\circ}$,the new angle for beam $A$ is $	heta_A = 30^{\circ}$ and for beam $B$ is $	heta_B = 90^{\circ} - 30^{\circ} = 60^{\circ}$.The intensities of the beams after passing through the polaroid are:$I_A' = I_A \cos^2(30^{\circ}) = I_A \left(\frac{\sqrt{3}}{2}ight)^2 = I_A \cdot \frac{3}{4}$$I_B' = I_B \cos^2(60^{\circ}) = I_B \left(\frac{1}{2}ight)^2 = I_B \cdot \frac{1}{4}$Given that the beams appear equally bright,$I_A' = I_B'$:$I_A \cdot \frac{3}{4} = I_B \cdot \frac{1}{4}$$\frac{I_A}{I_B} = \frac{1}{3}$

Similar Questions

Which of the following phenomena can be demonstrated by light,but not with sound waves in an air column?

Which of the following diagrams represents the variation of the electric field vector magnitude with time for a circularly polarized light?

If a polaroid is kept in the path of uniformly unpolarised light,the ratio of the intensity of the transmitted light to the intensity of the light when the polaroid was not kept in its path is:

Two polarizers are placed such that the angle between their transmission axes is $60^o$. If unpolarised light of intensity $I_0$ is incident on the first polarizer,then the transmitted intensity from the second polarizer will be

Vedclass Test Series

Exam Paper Generator

Online Exam Module