Medium MCQ +4 / -1 PYQ · JEE Mains 2021

The internal energy (U), pressure (P) and volume (V) of an ideal gas are related as U $=$ 3PV + 4. The gas is :

  1. A either monoatomic or diatomic.
  2. B monoatomic only.
  3. C polyatomic only. Correct answer
  4. D diatomic only.

Solution

U = 3PV + 4<br><br>$\Rightarrow$ ${{nf} \over 2}$RT = 3PV + 4<br><br>$\Rightarrow$ ${{f} \over 2}$PV = 3PV + 4<br><br>$\Rightarrow$ f = 6 + ${8 \over {PV}}$<br><br>Since degree of freedom is more than 6 therefore gas is polyatomic.

About this question

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

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