A compound pulley system allows Alan to lift the crate with less force due to its mechanical advantage, which is calculated by counting the ropes supporting the load.
The advantage of using a compound pulley in the situation where Alan needs to lift a crate to a storage shelf 5 meters high is that it allows Alan to lift the crate with less force. In physics, a compound pulley is a combination of several pulleys, which together function to reduce the effort force needed to lift an object. The mechanical advantage (MA) of a pulley system is calculated by counting the number of ropes supporting the load. When using a compound pulley system, more ropes means less force is needed to lift the object. However, this comes with the trade-off of pulling a greater length of rope to achieve the same vertical distance.