Using multiple pulleys in a system can provide a greater mechanical advantage, but it also means that the distance the rope needs to be pulled is .

A fixed pulley changes the direction of the force needed to lift an object, but does not change the amount of needed.

The main advantage of using pulleys is that they can help to reduce the amount of needed to lift an object.

A movable pulley changes both the direction of the force and the amount of force needed to lift an object. This makes it an example of a .

Pulleys are simple machines that help to lift heavy objects. They work by applying a force over a .

A block and tackle system uses multiple pulleys to provide an even greater for lifting heavy objects.