Recall the law of Malus I′=2Icos2θ
Here θ is the angle between two polaroids,
⇒83I=2Icos2θ⇒θ=30∘.
A source of light is placed in front of a screen. The intensity of light on the screen is I. Two Polaroids P1 and P2 are so placed in between the source of light and screen that the intensity of light on the screen is 2I. Then the P2, should be rotated by an angle of (degrees) so that the intensity of light on the screen becomes 83I.
Held on 26 Aug 2021 · Verified 6 Jul 2026.
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