1 There are two basic conditions for equilibrium. One pertains to the sum of all the forces on an object, while the other applies to the sum of the torques. What are these conditions? You should be able to express them in words, as well as writing them as equations. 2 Both conditions for equilibrium must be met for a system to be in equilibrium. What would happen if the net force was zero but there was a net torque? What would happen if the net torque was zero but there was a net force? 3 In this simulation five forces are shown on the free-body diagram. The positions of four of these, the two support forces and the weights of the two boxes, are easy to position on the free-body diagram. The other force is the weight of the beam. Where is this force placed on the free-body diagram? Why is it placed there, and why is it important to place each of the forces in its proper location along the beam? 4 If you and a friend are lifting a heavy piece of furniture, and your friend is much stronger than you are, which one of you should lift the furniture at one end and which one of you should be closer to the center-of-gravity?