JEE Main 2026 — Kinetic Theory of Gases Question with Solution
JEE Main 2026 (21 January Shift 2)
Question
The r.m.s. speed of oxygen molecules at is equal to that of the hydrogen molecules kept at . (Mass of oxygen molecule/mass of hydrogen molecule )
Choose an option
Show full solutionCorrect option: B
Correct answer
B-253
Step-by-step explanation
The root-mean-square speed of gas molecules is: , where is absolute temperature and is molar mass.
For oxygen at K with g/mol:
For hydrogen with g/mol at temperature :
Equating the RMS speeds:
K
Converting to Celsius: , which is option (2).
For oxygen at K with g/mol:
For hydrogen with g/mol at temperature :
Equating the RMS speeds:
K
Converting to Celsius: , which is option (2).
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This is a previous-year question from JEE Main 2026, covering the Kinetic Theory of Gases chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.