1. The problem statement, all variables and given/known data A block slides down a slope from point O with initial speed V. THe sliding coefficient, mu, brings the block to rest at time T. Using the ramp as the x-axis and the perpendicular as the y-axis, find T. 2. Relevant equations F = ma mu = mg sin(theta) a=dv/dt 3. The attempt at a solution I'm taking modern physics, and this is a problem to demonstrate how picking different frames of reference can change a problem. I have to take the axes as the vertical and horizontal after solving this part, butI haven't had general physics in about 3 years, so I'm just not sure how to do the easy part. I think if I get this part I can get the second, I just need a small refresher. I was thinking somewhere along the lines of this: ma = mg sin(theta) - mu dv/dt = g sin(theta) - mu/m dt = dv/(g sin(theta) - mu/m) Maybe? But, I'm not sure how I should do that derivative. Thanks!