Question

Calculate the moment of inertia of a uniform disc of mass 10 kg and radius 60 cm about an axis perpendicular to its length and passing through its centre.

Hint:

Use \( I = \frac{1}{2} M R^2 \) for a disc’s moment of inertia about its central perpendicular axis; convert units to SI.

Answer 1

For a uniform disc, the moment of inertia about an axis perpendicular to its plane through the center is: \[ I = \frac{1}{2} M R^2. \] Given: \( M = 10 \, \text{kg} \), \( R = 60 \, \text{cm} = 0.6 \, \text{m} \).
\[ I = \frac{1}{2} \cdot 10 \cdot (0.6)^2 = 5 \cdot 0.36 = 1.8 \, \text{kg} \cdot \text{m}^2. \] Answer: 1.8 kg m\(^2\).