1. The problem statement, all variables and given/known data A plum bob suspended from a frame settles to a steady position as the frame slides down a frictionless inclined plane. What is the angle the plumb bob makes with the vertical during the slide? 2. Relevant equations The problem is from a section introducing Newton's Laws. I assume this problem is about inertia. 3. The attempt at a solution Utterly no idea how to go about this, although I assume the answer is alpha=theta since that's the clean way the answer could come out.