The formula of internal energy of a gas is given by
U=2fRT
Here R is the gas constant and T is temperature.
(R=8.314Jmol−1K−1)
For the given configuration of triatomic molecules, the degree of freedom f=6
⇒U=26RT=3RT
JEE Main 2020 Physics, Kinetic Theory of Gases — question figure Consider a gas of triatomic molecules. The molecules are assumed to be triangular…
JEE Main 2020 — Physics Thermodynamics
2020mcqeasy
Consider a gas of triatomic molecules. The molecules are assumed to be triangular and made of massless rigid rods whose vertices are occupied by atoms. The internal energy of a mole of the gas at temperature T is:
Official previous-year question
Held on 3 Sept 2020 · Verified 6 Jul 2026.
Options
- A
25RT
- B
23RT
- C
29RT
- D
3RT
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