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For polyatomic molecules having 'f' vibrational modes, the ratio of two specific heats,Cp/Cv is..........

#### Options

`(1+f)/(2+f)`

`(2+f)/(3+f)`

`(4+f)/(3+f)`

`(5+f)/(4+f)`

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#### Solution

**`(4+f)/(3+f)`**

By the law of equipartition of energy, for one mole of polyatomic gas

`C_p=(4+f)R and C_v=(3+f)R`

`thereforeC_p/C_V=((4+f)R)/((3+f)R)=(4+f)/(3+f)`

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