posted by Christy .
A 75 kg box slides down a 25 degree ramp with an acc. of 3.6 m/s2. find mu,k between the box and the ramp.
Write down Newton's second law for the direction of motion. "a" is the acceleration.
Mg sin 25 - M g cos 25 *mu,k = M a
The first term is the weight component along the direction of motion and the second term is the friction force.
M cancels out. Solve for a.