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ISRO Scientist ME 2020 Paper

Option 2 : Helium

ST 1: Thermodynamics

2167

20 Questions
60 Marks
32 Mins

In case of gas, we get two specific heats. They are specific heat at constant pressure and specific heat at constant volume. The ratio of these two specific heats is given by γ. In case of object, the degrees of freedom mean the number of independent variables to understand the object.

For ideal gas (obeys PV = nRT law) the relation between specific heat ratio and degrees of freedom is γ = (f + 2)/f.

For example, a monatomic gas has three DOF, so we get γ = (3 + 2)/3 = 5/3.