Need some feedback on my attack strategy to the following: A cube of side L rests on a rough floor. It is subject to a steady horizontal pull, F, exerted a distance h above the floor. As F is increased, the block will either begin to slide, or begin to tip over. (a) What must be the coefficient of static friction so that the block begins to slide rather than tip? (b) What must be the coefficient of static friciton so that the block begins to tip? For (a): Let f be the force of friction. Is it sufficient to say that if the block begins to slide, then F - f > 0? Would it be wiser to calculate the torque about the tipping edge and set it equal to 0? For (b): I'm not exactly sure what to do here. I drew a free-body diagram of the situation, but I don't know how to place F (is it still acting horizontally?). I guess I should consider the instant the block begins to tip (so that F is still acting horizontally). If this is the case, should I calculate the torque about the tipping edge again (with the difference that the normal is now acting entirely from the tipping edge, unlike in (a)).