Physics Question Help?

Question

A 50.5kg crate is at rest on a level floor and the coeffecient of kinetic friction is 0.384. The accleration of gravity is 9.8m/s2. If the crate is pushed horizontally with a force of 279.361 newtons, how far does it move in 2.69s. (in meters)

Answer 1

The normal force is
Fn=ma=50.5*9.8=494.9 N
The frictional force is then
Ff=µk*Fn=.384*494.9=190N
If 279.361N are applied to the crate, the net force is
Fnet=Fa-Ff=279.36-190=89.36N so that the crate accelerates at
a = Fnet/m = 89.36/50.5 = 1.769 m/s² and it moves
s = (1/2)at² = (1/2)*1.769*2.69²=6.4 m

Doug