Question

A baseball player slides into third base with an initial speed of 8.55 m/s. If the coefficient of kinetic friction between the player and the ground is 0.45, how far does the player slide before coming to rest?

Answer 1

Vi=8.55m/s

Ff=Ukmg=0.45m(9.8m/s2)
Calculate the acceleration (which will be negative since it's due to the force of friction):
a=Fma=(0.45)(9.8m/s2)mma=4.41m/s2
Time to stop:t=8.55m/s4.41m/s2=1.94s
Now see how far they go in 1.94s with an acceleration of -4.41m/s^2:x=V0t+12at2x=(8.55m/s)(1.94s)+12(−4.41m/s2)(1.94s)2=8.29m