A 120-kg crate, starting from rest, is pulled across a floor with a constant horizontal force of 400 N. For the first 17 m the floor is frictionless, and for the next 17 m the coefficient of friction is 0.34. What is the final speed of the crate?

2 answers

Use
F=ma to find the acceleration
and
v²-u²=2aS
to find the final velocity v from an initial velocity u over a distance of S and acceleration a.

F=400 N for the first 17m
and F=400-μmg for the next 17m, where μ is the coefficient of kinetic friction.

Post what you get for a check if you wish.
0 j