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Question
The ratio Cp / Cv for a gas is 1.29. What is the degree of freedom of the molecules of this gas?
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Solution
For the molecules of a gas, `gamma = ("C"_"P")/("C"_"V") = 1+ 2/"f" `
where f is the degree of freedom.
Given : γ =1.29
`=> 1+2/"f" = 1.29 = 9/7`
`=> 2/"f" =9/7 -1`
`=> 2/"f" =2/7`
⇒ f =7
Therefore, the molecules of this gas have 7 degrees of freedom.
But in reality, no gas can have more than 6 degrees of freedom.
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