MHT CET · Physics · Kinetic Theory of Gases

For a gas, \(\frac{\mathrm{R}}{\mathrm{C}_{\mathrm{v}}}=0.4\) where R is the universal gas constant and ' \(\mathrm{C}_{\mathrm{v}}\) ' is molar specific heat at constant volume. The gas is made up of molecules which are

A rigid diatomic.
B monoatomic.
C non-rigid diatomic.
D polyatomic.

Verified Solution

Answer & Solution

Correct Answer

(A) rigid diatomic.

Step-by-step Solution

Detailed explanation

\(\begin{aligned}
& \text {Given: } \frac{R}{C_v}=0.4 \\
& C_V=\frac{R}{0.4}=\frac{5 R}{2} \\
& C_P=C_V+R \\
& \therefore \quad C_P=\frac{7 R}{2} \\
& \gamma=\frac{C_P}{C_v}=\frac{\frac{7}{2}}{\frac{5}{2}} \\
& \gamma=\frac{7}{5}
\end{aligned}\)
\(\therefore \quad\) The gas is made up of rigid diatomic molecules.

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.

Same subject

Explore more questions on app

From MHT CET

Explore more questions on app