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The Ratio Cp / Cv for a Gas is 1.29. What is the Degree of Freedom of the Molecules of this Gas? - Physics

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प्रश्न

The ratio Cp / Cv for a gas is 1.29. What is the degree of freedom of the molecules of this gas?

संक्षेप में उत्तर

उत्तर

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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Molecular Nature of Matter
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अध्याय 5: Specific Heat Capacities of Gases - Short Answers [पृष्ठ ७६]

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एचसी वर्मा Concepts of Physics Vol. 2 [English] Class 11 and 12
अध्याय 5 Specific Heat Capacities of Gases
Short Answers | Q 10 | पृष्ठ ७६

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