A block on a rough horizontal surface is pushed by a horizontal force F. The graph of acceleration a versus F is shown. Which statements are correct?

Question

G1 Physics · Accepted Answer

The graph remains at a=0 up to F=10 N, so limiting friction is 10 N. Beyond this point the slope da/dF = 1/m; from the graph the slope gives m=2 kg. Hence μ=10/(2×10)=0.5. For F=8 N the actual static friction is 8 N, not 10 N. Therefore A, B and C.