JEE Main202126 Aug 2021Evening ShiftPhysicsWave OpticsActual
A source of light is placed in front of a screen. The intensity of light on the screen is I . Two Polaroids P 1 and P 2 are so placed in between the source of light and screen that the intensity of light on the screen is I 2 . Then the P 2 , should be rotated by an angle of (degrees) so that the intensity of light on the screen becomes 3 I 8 .
Correct answer
30
Step-by-step solution
Recall the law of Malus I ' = I 2 cos 2 θ Here θ is the angle between two polaroids, ⇒ 3 I 8 = I 2 cos 2 θ ⇒ θ = 30 ° .