A block of mass 4.0 kg, which has an initial speed of 6.0 m/s, slides on a horizontal surface and eventually comes to rest from friction.
a. Calculate the work that must be done by friction on the block to bring it to rest.
b. If the friction force between the block and the surface has a magnitude of 88 N, how far will the block travel before stopping?
a. the work is equal to the initial kinetic energy of the block
... K.E. = 1/2 m v^2 = 1/2 * 4.0 kg * (6.0 m/s)^2 = ? Joules
b. work = force * distance
... distance = (answer a.) / 88 N = ? m