JEE Main 2024 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 30 January 2024, Shift 2, Physics Q45

Question 45 of 90 in this shift, Physics question 15 of 30, Section A.

A beam of unpolarised light of intensity

I_o

is passed through a polaroid

A

and then through another polaroid

B

which is oriented so that its principal plane makes an angle of

45^\circ

relative to that of

A

. The intensity of emergent light is:

(1) $I_o$
(2) $I_o/2$
(3) $I_o/4$ Official answer
(4) $I_o/8$

Official answer

Option 3

NTA final key.

Chapter: Wave Optics
Topic: Polarization
Idea tested: Malus's Law Calculation

Same idea in other shifts

Asked 3× in all

4 Apr 2026, Shift 2 · Q42An unpolarized light of certain intensity passes through a combination of two polarizers whose transmission axes are at $30^\circ$ and…MediumSingle correct
6 Apr 2026, Shift 1 · Q47An unpolarized light of intensity $I_0$ passes through polarizer and then through a certain optically active solution and finally it goes…MediumNumerical value

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.