NEET UG 2020 · Physics · Question 138
NEET 2020 Physics, question 138
Question 138 of the NEET 2020 paper (code E1) is a Physics question from Wave Optics. Its idea, Polarisation and Malus's Law, was asked 6 times, in 2017, 2018, 2020, 2024 and 2025, across NEET 2017–2026. The NTA final answer key gives option 3.
Updated 2026-10-08
Q138 · Physics
The Brewsters angle for an interface should be :
- 10° < < 30°
- 230° < < 45°
- 345° < < 90°Official answer
- 4 = 90°
Official answer: option 3 · NTA final answer key
Same idea
Polarisation and Malus's Law, in other papers
NEET asked this idea 6 times, in 2017, 2018, 2020, 2024 and 2025. The other 5 questions below.
- 2025 Q27An unpolarized light beam travelling in air is incident on a medium of refractive index 1.73 at Brewster's angle. Then-One-line MCQ · Easy
- 2025 Q43The intensity of transmitted light when a polaroid sheet, placed between two crossed polaroids at 22.5° from the polarization axis of one…Numerical · Medium
- 2024 Q2An unpolarised light beam strikes a glass surface at Brewster's angle. ThenOne-line MCQ · Easy
- 2018 Q8Unpolarised light is incident from air on a plane surface of a material of refractive index ''. At a particular angle of incidence…One-line MCQ · Medium
- 2017 Q37Two Polaroids and are placed with their axis perpendicular to each other. Unpolarised light is incident on . A…Numerical · Easy
Polarisation and Malus's Law: every question and how it was framed
The chapter
Wave Optics in ten years of NEET
15 questions from 2017–2026, asked in 8 of 10 papers, about 1.5 a paper. Single Slit Diffraction alone had 8.