By: Ali Lewis and Drew Johnson
Drew's Home Pulley System
This pulley system helps his family lift heavy objects into their attic that they cannot carry.
A pulley makes lifting a heavy object easier because it reduces the effort required to lift it. Although lifting becomes easier, you pull a rope that travels a greater distance than the height you lift the object. The extra distance decreases your effort by giving you mechanical advantage. Mechanical advantage depends of the number of ropes the pulley has to increase mechanical advantage you need to increase the number of support ropes. If you have three ropes you get three times as much force by pulling out three times as much rope. To find mechanical advantage you divide force in or effort by force out or resistance.
A pulley is used to raise a car. The pulley's input force of 400N is needed to provide an output force of 16,000N. What is the mechanical advantage of this pulley?
AMA= force out(resistance)/ force in (effort)
How Elevators and Pulleys Work
Working pulley system.