A constant horizontal force of magnitude 18.0 N pushes a block of mass 2.00 kg along

a rough horizontal surface for a distance of 2.00 m. During this operation the speed
of the block changed from 4.00 m/s to 6.00 m/s. What work was done on the block
by kinetic friction?
(a) 32 J (b) 16 J (c) 8 J (d) 4 J (e) 0 J

The Correct Answer is b) but I don't know how to get this.

Thanks for you help.

1 answer

Initial KE + work done=FinalKE
FinalKE-InitialKE=work done
1/2 m (6^2-4^2)=work done