1 mole of rigid diatomic gas performs a work of ${Q \over 5}$ when heat Q is supplied to it. The molar heat capacity of the gas during this transformation is ${xR \over 8}$. The value of x is _________. [R = universal gas constant]
Answer (integer)
25
Solution
From thermodynamics law:
<br><br>$Q = \Delta U + W$<br><br>$Q = \Delta U + {Q \over 5}$<br><br>$\Delta U = {{4Q} \over 5}$<br><br>$n{C_v}\Delta T = {4 \over 5}nC\Delta T$<br><br>${5 \over 4}{C_v} = C$<br><br>$$C = {5 \over 4}\left( {{f \over 2}} \right)R = {5 \over 4}\left( {{5 \over 2}} \right)R$$<br><br>$C = {{25} \over 8}R$<br><br>$X = 25$
About this question
Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law
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