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QJEEM20Ph3080: JEE Main 2020 Physics - Class 12 JEEM20Ph3080 Solution: A polarizer - analyser set is adjusted such that the intensity…

A polarizer - analyser set is adjusted such that the intensity of light coming out of the analyser is just 10% of the original intensity. Assuming that the polarizer - analyser set does not absorb any light, the angle by which the analyser need to be rotated further to reduce the output intensity to be zero, is :

Multiple Choice Options

  • A 71.6o
  • B 90o
  • C 18.4o
  • D 45o

Step-by-Step Verified Solution

I = I0 cos2 θ\theta

⇒\Rightarrow I010{{{I_0}} \over {10}} = I0 cos2 θ\theta

⇒\Rightarrow cos θ\theta = 110{1 \over {\sqrt {10} }}

⇒\Rightarrow θ\theta = 71.6o

∴\therefore ϕ\phi = 90 - 71.6 = 18.4o

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