Question

Plane polarized light is incident on an analyser. The intensity then becomes three fourth. The angle of the axis of the analyser with the polarization axis of beam is:

• A. ${30}^{\circ }$
• B. ${45}^{\circ }$
• C. ${60}^{\circ }$
• D. Zero

Answer 1

The correct option is C ${60}^{\circ }$

$I=I_{0}co{s}^2\theta$ $\therefore \frac{3}{4}{I}_0=I_{0}co{s}^2\theta$
$Cos\theta =\frac{\sqrt{3}}{2},\theta ={60}^{\circ }$
This is the angle, which the axis of analyser makes with vertical. Therefore the angle which the axis of analyser makes with light ray = ${60}^{\circ }$.