Introduction Before the industrial age people largely had to rely on muscle power to move and lift heavy objects. Simple machines such as pulleys, levers and ramps made it easier for humans to lift ...

Explains how pulleys work to lift heavy weights more easily. A fixed pulley changes the direction of force, allowing for easier lifting, while a movable pulley reduces the amount of force needed to ...

A weight machine is an exercise machine used for weight training that uses gravity as the primary source of resistance, and a combination of simple machines to convey that resistance to the person ...