How Elevators Work

Elevators use counterweights, which are powered via gravity to help move themselves. while elevators have engines to power their movement, but they are greatly aided with the use of counterweights. 

Counterweights use gravity to aid elevators with about 40-50 percent of their load. When the elevator goes up, the counterweight goes down and vice-versa. If the elevator is empty then there are brakes to slow down the force created by the counter weights. 

Of course, the counter weights are unable to power the elevator fully meaning that you still have to use other parts to move the elevator. Counterweights in elevators have been used to aid in lifting people up high buildings. 

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