JEE Main 2021 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 26 August 2021, Shift 2, Physics Q26

Question 26 of 90 in this shift, Physics question 26 of 30, Section B.

A source of light is placed in front of a screen. Intensity of light on the screen is I. Two Polaroids

\mathrm{P_1}

and

\mathrm{P_2}

are so placed in between the source of light and screen that the intensity of light on screen is I/2.

\mathrm{P_2}

should be rotated by an angle of __________(degrees) so that the intensity of light on the screen becomes

\frac{3I}{8}

Official answer

NTA final key.

Chapter: Wave Optics
Topic: Polarization
Idea tested: Intensity Halving of Unpolarized Light

Same topic in other shifts

All Polarization questions

4 Apr 2026, Shift 1 · Q45An unpolarized light is incident on the plane interface of air-dielectric medium shown in figure. If the incident angle is equal to…HardDiagram basedHas a figure
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
4 Apr 2025, Shift 2 · Q40Two polarisers $P_1$ and $P_2$ are placed in such a way that the intensity of the transmitted light will be zero. A third polariser $P_3$ …MediumSingle correct
30 Jan 2024, Shift 2 · Q45A beam of unpolarised light of intensity $I_o$ is passed through a polaroid $A$ and then through another polaroid $B$ which is oriented so…EasySingle correct
31 Jan 2024, Shift 2 · Q45When unpolarized light is incident at an angle of $60^\circ$ on a transparent medium from air, the reflected ray is completely polarized.…EasySingle correct

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 108 of the 174 JEE Main shifts held from 2017 to 2026.