1. The problem statement, all variables and given/known data A cubical block of side L rests on a fixed cylindrical drum of radius R. Find the largest value of L for which the block is stable. 2. Relevant equations 3. The attempt at a solution There is only one contact point between the cube and cylinder. There are three forces acting on the cube. The normal reaction from the cylinder, the friction and weight. The normal reaction and the friction pass through the contact point. Now how do I form the equations here? Any help is appreciated. Thanks!