Easy MCQ +4 / -1 PYQ · JEE Mains 2021

A diatomic gas, having ${C_p} = {7 \over 2}R$ and ${C_v} = {5 \over 2}R$, is heated at constant pressure. The ratio dU : dQ : dW :

  1. A 5 : 7 : 3
  2. B 3 : 7 : 2
  3. C 5 : 7 : 2 Correct answer
  4. D 3 : 5 : 2

Solution

$dV = n{5 \over 2}R\Delta T$<br><br>$dQ = n{7 \over 2}R\Delta T$<br><br>$dW = dQ - dV$<br><br>$= n{2 \over 2}R\Delta T$<br><br>$\therefore$ $dV:dQ:dW$<br><br>$= n{5 \over 2}R\Delta T:n{7 \over 2}R\Delta T:n{2 \over 2}R\Delta T$<br><br>$= 5:7:2$

About this question

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

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