What is the original kinetic energy of the player?

[needhelp83]

A 95-kg football player traveling 5.0 m/s is stopped in 1.0 s by a tackler.
a. What is the original kinetic energy of the player?
b. What average power is required to stop him?

a.
K=(1/2)mv2
K=(1/2)(9500 g)(5.0 m/s)2= 118,750 J
b.
P=w/t
P=118750 J/1.0 s= 118750 W


Would this be correct because of the work-energy principle?

 

[radou]

Looks okay, but I don't see why you should convert [kg] to [g].