In a two tourmalines experiment, the polariser and analyser are crossed with each other. At what angle should the analyser be rotated so that 25% of light passes through analyser ?

In a two tourmalines experiment, the polariser and analyser are crosse

1.	In a two tourmalines experiment, the polariser and analyser are crossed with each other. At what angle should the analyser be rotated so that 25% of light passes through analyser ?
Answer» `60^(@)` `90^(@)` `30^(@)` `45^(@)` Solution :From Malus LAW, `I=I_(0) cos^(2) theta"" [ I=I_(0),25%=(I_(0))/(25)]` `(I_(0))/(4)=I_(0) cos^(2) theta` `(1)/(2) cos theta :. theta=60^(@)` `:.` Analyswer should be ROTATES at `(90^(@)-60^(@))=30^(@)` angle.

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In a two tourmalines experiment, the polariser and analyser are crossed with each other. At what angle should the analyser be rotated so that 25% of light passes through analyser ?

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