Medium MCQ +4 / -1 PYQ · JEE Mains 2020

In an adiabatic process, the density of a diatomic gas becomes 32 times its initial value. The final pressure of the gas is found to be n times the initial pressure. The value of n is :

  1. A 128 Correct answer
  2. B 32
  3. C 326
  4. D ${1 \over {32}}$

Solution

In adiabatic process <br><br>PV<sup>$\gamma$</sup> = constant <br><br>$\Rightarrow$ $P{\left( {{m \over \rho }} \right)^\gamma }$ = constant <br><br>As mass is constant <br><br>$\therefore$ P $\propto$ ${{\rho ^\gamma }}$ <br><br>$\Rightarrow$ $${{{P_f}} \over {{P_i}}} = {\left( {{{{\rho _f}} \over {{\rho _i}}}} \right)^\gamma }$$ = ${\left( {32} \right)^{{7 \over 5}}}$ = 2<sup>7</sup> = 128 <br><br>[ For diatomic gas $\gamma$ = ${{7 \over 5}}$ ]

About this question

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

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