A 7.80-g bullet moving at 590 m/s penetrates a tree trunk to a depth of 4.8 cm. Assuming the friction force is constant, determine how much time elapses between the moment the bullet enters the tree and the moment it stops moving.

Answer 1

Vo=0
7.80g=.0078kg
V=590m/s
d=.048m

W/d
W=Fd
=1/2mV^2 - 1/2m(Vo)^2

Answer 2

Forgot to clarify W/d is the total Force. Where W=KE=1/2mV^2