Friction Problem: Find Time to Rest w/ Force of 5.0 N

[Lobos Wolfen]

I have a question on a Friction problem I have received. The question is, If the force acting on the two bricks is 5.0 N, how much time will elapse before the bricks come to rest.

Infomation given- The two bricks are sliding together, the wieghts are 24.5 N and 36.8 N, they are moving at a speed of 1.77 m/sec.

 

[Doc Al]

Is 5.0 N the friction force? If so, figure out the acceleration of the bricks using Newton's 2nd law.