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Three objects, A : (a solid sphere), B : (a thin circular disk) and C : (a circular ring), each have the same mass M and radius R. They all spin with the same angular speed $\omega$ about their own symmetry axes. The amounts of work (W) required to bring them to rest, would satisfy the relation
Explanation
Work equals rotational KE, which is proportional to moment of inertia.
Detailed Solution
Work done required to bring them to rest $W = \Delta KE$
$W = \frac{1}{2}I\omega^2 \Rightarrow W \propto I$ for same $\omega$
$W_A : W_B : W_C = \frac{2}{5}MR^2 : \frac{1}{2}MR^2 : MR^2 = \frac{2}{5} : \frac{1}{2} : 1 = 4 : 5 : 10$
$\therefore W_C > W_B > W_A$