Balances mechanics (also known as the Law of Balance) is a law that says that if an object has the same amount of weight on both sides, then it will be balanced. This means that if you place an object on a flat surface and then arrange the weight on either side of the object, the object will stay still. For example, if you place a block on a seesaw and place the same amount of weight on either side of the block, the seesaw should stay still.