Which type of pulley provides a mechanical advantage?

A movable pulley is designed to provide a mechanical advantage by allowing the user to lift a load with less effort compared to lifting it directly. This is achieved because the load is supported by the pulley, effectively distributing the weight and reducing the amount of force needed to move it.

In a movable pulley system, one end of the rope is fixed, and when you pull down on the other end, the pulley rises along with the load. This configuration means that you have to exert half the force to lift the load, as you are effectively using the pulley system to change the direction of the force and share the load.

Other types of pulleys also have their uses, but they do not provide a mechanical advantage in the same way that a movable pulley does. A fixed pulley, for example, changes the direction of the force applied but does not reduce the effort needed to lift the load. Compound and block and tackle systems include both fixed and movable pulleys, and while they can also provide mechanical advantages, the simplest form is represented by the movable pulley alone.