Pulley systems are simple machines that make lifting heavy objects easier. They consist of a rope or cable that passes over one or more wheels (pulleys). A single pulley changes the direction of force ...

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 ...

A gear close gearA gear is a mechanical part with teeth that interlock with another gear or belt to transfer motion and power while changing speed, or direction in a mechanical system. is a special ...

The Ancient Greeks may have invented an intricate pulley system of ropes and levers to lift vast blocks weighing up to 900 lbs when building their enormous structures. In the sixth century BC, the ...