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Kinetic Theory of Gases appeared 26 times across 3 years — 3% of Physics. This question is from RMS Velocity of Gases.

Year 2026 2025 2024 Total
Questions 6 11 9 26
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At which temperature the r.m.s. velocity of a hydrogen molecule equal to that of an oxygen molecule at 47°C?

Solution & Explanation

Related Formula
vrms = √((3RT)/(M))
Core Logic

For the RMS velocities to be equal, the ratio of temperature to molar mass (T/M) must be identical for both gases.

Step 1: Set Up Equivalency
3RTH₂MH₂ = 3RTO₂MO₂ TH₂MH₂ = TO₂MO₂
Step 2: Substitute Values

TO₂ = 47^ = 47 + 273 = 320 ~K MH₂ = 2 ~g/mol MO₂ = 32 ~g/mol

TH₂2 = (320)/(32) TH₂ = 2 × 10 = 20 ~K
Pattern Recognition

vrms scales strictly as √(T/M). Remember to always convert Celsius to Kelvin before substituting.

Chapter Mix

Class 11 Physics: Kinetic Theory of Gases

Reference Study Guides

Kinetic Theory Of Gases

More Kinetic Theory of Gases Previous-Year Questions — Page 6

Q31 jee_main_2024_31_jan_morning Kinetic Energy Of Gas Molecules
The parameter that remains the same for molecules of all gases at a given temperature is :
  • A. kinetic energy
  • B. momentum
  • C. mass
  • D. speed

Solution

Related Formula
KE = (f)/(2)kT
Core Logic

The average translational kinetic energy of any gas molecule depends only on the absolute temperature of the gas and is independent of the nature or mass of the gas.

For 1 mole of any ideal gas, the average translational kinetic energy is (3)/(2)RT. Therefore, at a given temperature, the kinetic energy parameter is uniform across all ideal gases.

Pattern Recognition

Temperature is directly proportional to average translational kinetic energy. If T is constant, KE is constant for all gases regardless of mass.

Chapter Mix

Class 11 Physics: Kinetic Theory

More Kinetic Theory of Gases Questions — jee_main_2024_30_jan_morning

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Rankbit System
JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%) | JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%)