Question

If an object is moving at `1 m/s` over a surface with a kinetic friction coefficient of `u_k=5 /g`, how far will the object continue to move?

Answer 1

0,1 m

Explanation:

The friction force that opposite to the movement is
`F= mu_k xx m xx g=5 m`
the deceletaion given by the friction force, from the second dynamic law is:
`a= F/m= 5 m/m = 5m/s^2`
from the movement law
`v = a xx t`
you have
`t= v/a = (1 m/s )/(5 m/s^2)= 0,2 s`
and
`s = v° xx t - 1/2 a xx t^2 = 1m/s xx 0,2 s -0.5 xx5 m/s^2 xx (0.2 s)^2= 0,2 m-0,1 m = 0,1 m`