Work occurs when a force causes an object to move from earth's surface. Work=force X Distance . Distance is the when the object moves above earth's surface .Simple machines are the most basic machines. scientists divide the six simple machines into two families. A pulley is a kind of machine in the lever family. A compound machine is a machine that combine two or more simple machines.
Energy is the ability to do work whenever work is done , energy is transformed or transferred from one object to another object. Potential energy is the energy an object has because of its position or shape. Potential energy is sometimes called energy of positions because its results from the relative positions of objects . Kinetic Energy is the energy of an object has because it is moving. Mechanical Energy the amount of work something can do because of its kinetic and potential energies.