JEE Main 2018PhysicsWave OpticsMediumMCQ

JEE Main 2018 — Wave Optics Question with Solution

JEE Main 2018 (08 Apr)

Question

Unpolarized light of intensity I passes through an ideal polariser A. Another identical polariser B is placed behind A. The intensity of light beyond B is found to be I2. Now another identical polariser C is placed between A and B. The intensity beyond B is now found to be I8 . The angle between polariser A and C is

Choose an option

Show full solutionCorrect option: D
Correct answer
D45°

Step-by-step explanation



Transformation axis A and B are parallel. If the transformation axis of C is making angle θ with A, it will make angle 90−θ with B. Therefore,

⇒I2cos2θcos2(90−θ)=I8⇒14sin22θ=14
⇒2θ=π2⇒θ=π4

Practice this on the real CBT interface

Solve this JEE Main question (and the rest of the Wave Optics chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.

Solve interactively →

About this question

This is a previous-year question from JEE Main 2018, covering the Wave Optics chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.