A sled of mass in is being pulled horizontally by a constant horizontal fora of magnitude F. The coefficient of kinetic friction is ? _k . During the time interval ?t = t, the sled moves a distance s. starting from rest. Part A Find the work W done by the force P. Express your answer in terms of the given quantities and, if necessary, appropriate constants. You may or may not use all of the given quantities (F, m, ? _k , t, s).

W = Fs

Find the average power P _avg created by the force F in terms of the average speed v _avg of the sled.

Express your answer in terms of F and V _avg .

10 X.10n HIT WELLA b t x x x X --- X ? X