Physics - Rotation Question with Solution | TestHub

For ring$1$and$2$using parallel axis theorem,

$I_1=I_2=I_{cm}+M{d}^2$

$I_1=I_2=\frac{1}{2}P{Q}^2+P{Q}^2$

$I_1=I_2=\frac{3}{2}P{Q}^2$

For ring$3$,

$I_3=\frac{1}{2}P{Q}^2$

Moment of inertia of the arrangement,

$I=I_1+I_2+I_3$

$I=\frac{3}{2}P{Q}^2+\frac{3}{2}P{Q}^2+\frac{1}{2}P{Q}^2$

$I=\frac{7}{2}P{Q}^2$