1. Tardigrade
  2. Question
  3. Physics
  4. Two circular discs are of same thickness. The diameter of A is twice that of B. The moment of inertia of A as compared to that of B is

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. Two circular discs are of same thickness. The diameter of $A$ is twice that of $B$. The moment of inertia of $A$ as compared to that of $B$ is

System of Particles and Rotational Motion

Solution:

Mass of disc $\propto$ area, $M_{A}=4 M_{B}$ (as $R_{A}=2 R_{B}$ )
$\frac{I_{A}}{I_{B}}=\frac{\frac{1}{2} M_{A} R_{A}^{2}}{\frac{1}{2} M_{B} R_{B}^{2}}=\frac{4 M_{B} \times\left(2 R_{B}\right)^{2}}{M_{B} \times R_{B}^{2}}=16$