Aforce of 300n[s] is applied to a 50kg box on a rough floor. the frictional force is 200n. the acceleration is 2m/s^2.
if the 300n force is removed after 4.0s, how long will it take the box to come to rest?
show all your work!

We want to know how far this box will move after the force stops. This is called the displacement and it can be calculated using:



We do not know the final velocity of the box however this can be calculated using:



When we put our values into this equation we get:




We can put this value into the Displacement equation to get




This means that the total difference in space between where the box stopped receiving a force and came to halt is 32m. Presuming the floor was completely flat, then the only way the box could move is forwards. This means that there is a 32m movement forwards between the two places which means the box took 32m to come to rest.