1. The problem statement, all variables and given/known data Need to find the time t taken for m to reach the bottom 2. Relevant equations F = ma 3. The attempt at a solution I don't know how to go about solving this from an inertial frame. In my view, the only two forces acting on this block are mg, which has a mgsin(theta) component along the plane and the normal force acting on the block however, the normal force has no component along the plane and hence it wouldn't affect the acceleration. This gives an acceleration of gsin(theta) which I know is the wrong answer. This question is easy to solve when we're in the FOF of the elevator ie an accelerated frame but I'm not able to figure out how to solve for the acceleration from an inertial frame. Once the acceleration is found the rest of the problem is pretty straightforward.