Q. The moment of inertia of a metre scale of mass $0.6\ kg$ about an axis perpendicular to the scale and located at the $20\ cm$ position on the scale in $kg\ m^{2}$ is (Breadth of the scale is negligible)

A) 0.074
B) 0.104
C) 0.148
D) 0.208
Explanation

(b) $I = I_{cm} + mx^{2} = \frac{ml^{2}}{12} + mx^{2} = m\left( \frac{(1)^{2}}{12} + (0.3)^{2} \right)$
$= 0.6\left( \frac{1}{12} + 0.09 \right) = 0.104\ kg - m^{2}$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.