AIIMS 2017 Physics Coefficient of Friction MCQ Question

The coefficient of friction ($\mu$) between the stick and the ring is given as $\frac{F}{10}$. To determine $F$, we need to consider the forces acting on the stick; if the maximum static friction force is equal to the weight of the stick, then $F$ must be 20 N, making $\mu = \frac{20}{10} = 2$. Thus, option A (2 N) is correct as it satisfies the condition for static friction.

Options B (4 N), C (6 N), and D (3 N) do not satisfy the relationship defined by the coefficient of friction and the forces involved, as they would imply a higher or lower friction than what is necessary to maintain equilibrium.