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Saturday, 31 October

JEE Main · Physics · Wave Optics

Invariance of Frequency in Refraction

JEE Main asked Invariance of Frequency in Refraction 2 times in 2 of the 108 shifts Lumi analysed, in 2022 and 2025. It belongs to Refraction and Snell's Law, in Wave Optics (Physics). The longest wait between two years asking it was 3 years.

Updated 2026-10-24

Times asked
2
in 2 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.

00.10.20’170’200’210.03’220’230’240.13’250’26

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: 1 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
  • 20251 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

Single correct is the usual form. Skill tested: calculation.

  • Wavelength in medium from frequency
  • Change in wave properties on refraction

Difficulty

Easy 2Medium 0Hard 0

Every question was multiple choice.

Every question

All 2 questions

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

  1. 3 Apr 2025, Shift 2 · Q42A monochromatic light of frequency 5×10145 \times 10^{14} Hz travelling through air, is incident on a medium of refractive index '2'.…EasySingle correct
  2. 27 Jun 2022, Shift 2 · Q47If a wave gets refracted into a denser medium, then which of the following is true?EasySingle correct

Shifts: 27 Jun 2022, Shift 2, 3 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