Easy MCQ +4 / -1 PYQ · JEE Mains 2023

According to law of equipartition of energy the molar specific heat of a diatomic gas at constant volume where the molecule has one additional vibrational mode is :-

  1. A $\frac{9}{2}R$
  2. B $\frac{5}{2}R$
  3. C $\frac{3}{2}R$
  4. D $\frac{7}{2}R$ Correct answer

Solution

Diatomic gas molecules have three translational degree of freedom, two rotational degree of freedom \& it is given that it has one vibrational mode so there are two additional degree of freedom corresponding to one vibrational mode, so total degree of freedom $=7$<br/><br/> $\mathrm{C}_{\mathrm{v}}=\frac{\mathrm{fR}}{2}=\frac{7 \mathrm{R}}{2}$

About this question

Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law

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