A 95.9-kg baseball player slides into second base. The coefficient of kinetic friction between the player and the ground is ìk = 0.554. (a) What is the magnitude of the frictional force? (b) If the player comes to rest after 1.63 s, what is his initial speed?

Answer 1

Wp = m*g = 95.9kg * 9.8N/kg = 940 N. =
Wt. of player.

a. Fk = 0.554 * 940 = 520.7 N.

Answer 2

b. Fn = m*a
a = Fn/m = (940-521)/95.9 = 4.37m/s^2.

V = Vo + a*t = 0
Vo = -a*t = -(-4.37*1.63) = 7.1 m/s.