If one mole of the polyatomic gas is having two vibrational modes and $\beta$ is the ratio of molar specific heats for polyatomic gas $\left( {\beta = {{{C_P}} \over {{C_V}}}} \right)$ then the value of $\beta$ is :
Solution
For polyatomic gas molecule has 3 rotational degrees of freedom,
3 translational degrees of freedom, and 2 vibrational modes.
<br/><br/>So, number of vibrational degrees of freedom = 2 $\times$ 2 = 4
<br/><br/>Degree of freedom of polyatomic gas<br><br>f = T + R + V<br><br>f = 3 + 3 + 4 = 10<br><br>$\beta = 1 + {2 \over f} = 1 + {2 \over 10}$<br><br>$\beta = {{12} \over 10} = 1.2$
About this question
Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law
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