Question

An object with a mass of 32 kg has an initial energy of 500 J. At the end of the experiment, the velocity of the object is recorded as 5.1 m/s. If the object travelled 50 m to get to this point, what was the average force of friction on object during the trip? Assume no potential energy.
I've bee stuck on this question, can whoever helps me show the work behind it? I have a lot of practice questions like this and I want to be able to do them myself.

Answer 1

final K.E = 1/2 * 32 * 5.1^2

work = (initial K.E.) - (final K.E.)

also ... work = force * distance = f * 50 m
... substitute the work value and solve for f

Answer 2

I don't understand @R_scott