Problem 6-47 Dynamics with friction - Part 6

A boy drags a huge garbage can of mass \(27\; kg\) along a horizontal driveway at a constant speed of \(1.8\; m/s\). He exerts a force of \(112\; N\) at an angle of \(27^\circ\) above the horizontal. Determine the coefficient of kinetic friction between the can and the driveway.

Accumulated Solution

FBD with all angles, directions and forces indicated.

\(\mu_K = F_K/F_N \\ a_y = 0 \\ F_N + F \sin \theta - mg = 0 \\ F_N = 214 \;N\)

\(F_N = mg - F \sin \theta = (27)(9.8) - (112) \sin\; 27 = 214\; N\)

What is the acceleration in the \(x\) direction?

(A)   \(0\)

(B)   \(g\)

(C)   \(-g\)