AIIMS 2018 Physics Friction MCQ Question

When the block is stationary with the ball, the weight (W) acting downwards must be balanced by the normal force (N) and any frictional forces. In option D, W = 2 N indicates that the weight of the ball is precisely balanced by the forces acting on it, allowing the system to remain stationary.

Option A (f = W) is incorrect because it implies that the frictional force equals the weight, which is not necessarily true unless specified. Option B (μN = W) is also incorrect as it suggests that the frictional force is equal to the weight, which is not the case for a stationary object unless friction is at its maximum. Option C (0.2(10 N) = W) incorrectly assumes a specific coefficient of friction without context, making it irrelevant to the problem.