physics problem for you?
A block is pushed across a rough horizontal surface from point A to point B by a force F = 5.4 N, as shown. The magnitude of the force of friction acting on the block between A and B is 1.2 N and points A and B are 0.5 m apart. If the kinetic energies of the block at A and B are 4 J and 5.6 J, respectively,
a) How much work is done on the block by the force F between A and B?
b) How much work is done on the block by the force of friction as the block moves between the two points?
Additional Details
note : there is an angle between the force and the surface
Comments
Work done by the force = increase in KE plus friction energy loss
increase in KE = 5.6 - 4 = 1.6 J
friction energy loss = Friction force x distance moved = 1.2N*0.5m = 0.6 J
work done = 2.2 J
Work done on the block by friction = -0.6 J