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Saturday, 31 October

JEE Main · Physics · Ray Optics and Optical Instruments

Refractive Index and Speed

JEE Main asked Refractive Index and Speed 3 times in 3 of the 108 shifts Lumi analysed, in 2022 and 2025. It belongs to Refraction and Snell's Law, in Ray Optics and Optical Instruments (Physics). The longest wait between two years asking it was 3 years. In 2025 it came in more than one shift of the same year.

Updated 2026-10-24

Times asked
3
in 3 shifts
Years
2 of 8
First asked
2022
last in 2025
Pattern
Occasional
across the analysed shifts

Questions on this idea a shift, by year

2017–2026. Asked in 2022 and 2025. Years differ in how many shifts Lumi analysed, so each year is scaled to one shift of 25 Physics questions.

00.150.30’170’200’210.03’220’230’240.25’250’26

Raw count: 2017: 0 in 1 shift · 2020: 0 in 12 shifts · 2021: 0 in 24 shifts · 2022: 1 in 24 shifts · 2023: 0 in 12 shifts · 2024: 0 in 18 shifts · 2025: 2 in 8 shifts · 2026: 0 in 9 shifts.

Shift by shift

Each square is one analysed shift, in date order. Open a filled one for that paper.

  • 20260 of 9
  • 20252 of 8
  • 20240 of 18
  • 20230 of 12
  • 20221 of 24
  • 20210 of 24
  • 20200 of 12
  • 20170 of 1

Asked in that shift More than once Not asked

How JEE Main framed it

Assertion–reason is the usual form. Skill tested: calculation.

  • Assertion-reason on refractive index and optical density
  • Light speed ratio from permeability and permittivity

Difficulty

Easy 1Medium 2Hard 0

1 of the 3 questions had a numerical answer.

Every question

All 3 questions

From the official JEE Main shift papers, newest first. Open one for the full question, the options and the official answer.

  1. 7 Apr 2025, Shift 2 · Q41Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Refractive…EasyAssertion–reason
  2. 4 Apr 2025, Shift 2 · Q47If an optical medium possesses a relative permeability of 10π\frac{10}{\pi} and relative permittivity of 10.0885\frac{1}{0.0885}, then the…MediumNumerical value
  3. 25 Jun 2022, Shift 1 · Q49The difference of speed of light in the two media A and B (vA−vBv_A-v_B) is 2.6×1072.6\times10^7 m/s. If the refractive index of medium B is 1.47,…MediumSingle correct

Shifts: 25 Jun 2022, Shift 1, 4 Apr 2025, Shift 2, 7 Apr 2025, Shift 2.

Same topic

Other ideas in Refraction and Snell's Law

Refraction and Snell's Law has 18 ideas JEE Main has asked; 8 of them came up in more than one question. The 12 most asked are below.

Topic analysisChapter analysisStudy this chapterAll repeated ideas