# What Is the Mechanical Advantage of Single Movable Pulleys?

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Pulleys are one of six types of simple machines, a device that allows people to accomplish work with less effort than the task would otherwise require. Simple machines allow this to happen due to their mechanical advantage, which provides a multiplier effect on the effort exerted. A moveable pulley is a type of pulley that moves with the object being moved.

Mechanical advantage is the name given to the force multiplier given by a simple machine. A machine’s mechanical advantage is essentially a measure of how much the required force is spread throughout the machine. Mechanical is a force multiplier because it multiplies the amount of effort you exert. For example, if a box required 100 newtons of force to move it, and you attached it to a pulley with a mechanical advantage of 3, you would only need to apply 33 newtons of force, because 33 times 3 equals 99, which is close enough to 100.

## Pulley

All pulleys have two components: a rope and a grooved wheel. The rope fits around the wheel, allowing the rope to move around it. Pulleys are either fixed or moveable. A fixed pulley is stationary, attached to a wall or similar object. The weight moved by the pulley is attached to the rope. The wheel of a moveable pulley is not attached to any stationary object; one end of the rope is stationary instead. In a moveable pulley, the weight is attached to the wheel rather than the rope, and the wheel moves along the length of the rope as the weight is lifted or lowered.

## Moveable Pulley

The mechanical advantage of a moveable pulley is 2. This means that a moveable pulley will halve the required force needed to move any object attached to it. This occurs because in a moveable pulley one end of the rope is stationary, which means it absorbs some of the force needed to move the object. So, if you attach a 100 newton box to a moveable pulley, you will only need to apply 50 newtons of force to move the box because the moveable pulley will multiply your force by 2.