MHT CET · Physics · Rotational Motion

A ring and a disc have same mass and same radius. The ratio of moment of inertia
of a ring about a tangent in its plane to that of the disc about its diameter is

A \(6: 1\)
B \(4: 1\)
C \(2: 1\)
D \(8: 1\)

Verified Solution

Answer & Solution

Correct Answer

(A) \(6: 1\)

Step-by-step Solution

Detailed explanation

Moment of inertia of a ring about a tangent in its plane is given by \(I=\frac{3}{2} M R^{2}\)
Moment of inertia of a disc about its diameter is given by \(I^{\prime}=\frac{1}{4} M R^{2}\)
\(\therefore \frac{I}{I^{\prime}}=6\)

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

A ring and a disc have same mass and same radius. The ratio of moment of inertiaof a ring about a tangent in its plane to that of the disc about its diameter is

Step-by-step Solution

A ring and a disc have same mass and same radius. The ratio of moment of inertia
of a ring about a tangent in its plane to that of the disc about its diameter is