Learn

Saturday, 31 October

JEE Main · Physics · Kinetic Theory

Molecular Speed Ratios

JEE Main asked Molecular Speed Ratios 8 times in 8 of the 108 shifts Lumi analysed, in 2021, 2022, 2023 and 2024. It belongs to Kinetic Theory of Gases, in Kinetic Theory (Physics). The longest wait between two years asking it was 1 year. In 2021, 2022 and 2024 it came in more than one shift of the same year.

Updated 2026-10-24

Times asked
8
in 8 shifts
Years
4 of 8
First asked
2021
last in 2024
Pattern
Comes in cycles
across the analysed shifts

Questions on this idea a shift, by year

2017–2026. Asked in 2021, 2022, 2023 and 2024. Years differ in how many shifts Lumi analysed, so each year is scaled to one shift of 25 Physics questions.

00.050.10’170’200.10’210.07’220.07’230.09’240’250’26

Raw count: 2017: 0 in 1 shift · 2020: 0 in 12 shifts · 2021: 3 in 24 shifts · 2022: 2 in 24 shifts · 2023: 1 in 12 shifts · 2024: 2 in 18 shifts · 2025: 0 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
  • 20250 of 8
  • 20242 of 18
  • 20231 of 12
  • 20222 of 24
  • 20213 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.

  • Rms speed ratio by molar mass
  • Ratio of rms speeds of two gases

Difficulty

Easy 6Medium 2Hard 0

1 of the 8 questions had a numerical answer.

Every question

All 8 questions

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

  1. 1 Feb 2024, Shift 2 · Q39If the root mean square velocity of hydrogen molecule at a given temperature and pressure is 2 km/s, the root mean square velocity of…EasySingle correct
  2. 6 Apr 2024, Shift 1 · Q37A sample contains mixture of helium and oxygen gas. The ratio of root mean square speed of helium and oxygen in the sample, is :EasySingle correct
  3. 13 Apr 2023, Shift 1 · Q39The rms speed of oxygen molecule in a vessel at particular temperature is (1+5x)12v\left(1+\frac{5}{x}\right)^{\frac{1}{2}} v, where vv is the…MediumSingle correct
  4. 28 Jun 2022, Shift 2 · Q39What will be the effect on the root mean square velocity of oxygen molecules if the temperature is doubled and oxygen molecule dissociates…MediumSingle correct
  5. 25 Jun 2022, Shift 1 · Q37The relation between root mean square speed (vrmsv_{rms}) and most probable speed (vpv_p) for the molar mass M of oxygen gas molecule at the…EasySingle correct
  6. 18 Mar 2021, Shift 2 · Q1Consider a sample of oxygen behaving like an ideal gas. At 300 K, the ratio of root mean square (rms) velocity to the average velocity of…EasySingle correct
  7. 27 Aug 2021, Shift 2 · Q8If the rms speed of oxygen molecules at 0∘C0^\circ\mathrm{C} is 160 m/s, find the rms speed of hydrogen molecules at 0∘C0^\circ\mathrm{C}.EasySingle correct
  8. 4 Aug 2021, Shift 1 · Q26The ratio of average speed to the rms speed of oxygen molecule is 8xπ\sqrt{\frac{8}{x\pi}} . The value of ‘x’ is ________ .EasyNumerical value

Shifts: 18 Mar 2021, Shift 2, 4 Aug 2021, Shift 1, 27 Aug 2021, Shift 2, 25 Jun 2022, Shift 1, 28 Jun 2022, Shift 2, 13 Apr 2023, Shift 1, 1 Feb 2024, Shift 2, 6 Apr 2024, Shift 1.

Same topic

Other ideas in Kinetic Theory of Gases

Kinetic Theory of Gases has 22 ideas JEE Main has asked; 14 of them came up in more than one question. The 12 most asked are below.

Topic analysisChapter analysisStudy this chapterAll repeated ideas