Question

A block of mass m is moving on a rough horizontal surface where coefficient of friction between block and surface is µ = 0.5. At t = 0 block is moving with a velocity $\overset{\rightarrow}{v}$ then a horizontal force F = 2t is applied on it in the direction of velocity. Here t represent time then the speed of block after the application of force-

• A. Decreases
• B. Increases
• C. First decreases then increases
• D. First increases then decreases

Answer 1

Answer: (C)

First decreases then increases

Answer 2

F_Net = F – f_k = 2t – mmg