## College Physics (4th Edition)

The force of friction acting on the suitcase is $12.5~N$
Since the suitcase is moving at a constant speed, the force of friction $F_f$ is equal in magnitude to the horizontal component of the applied force $F$. We can find the force of friction: $F_f = F~sin~\theta$ $F_f = (25.0~N)~sin~30.0^{\circ}$ $F_f = 12.5~N$ The force of friction acting on the suitcase is $12.5~N$