From DT Online
Features and Applications
In an ideal world, mechanical advantage and velocity ratio would always equal each other on a given system. In other words, if you lifted a car through 5cm by moving the jack handle through 500cm then the effort required would be one hundredth of the weight of the car.
Unfortunately, in the real world, friction, air resistance and other losses mean that this ideal situation is never actually achieved.
Efficiency = MA/VR x 100%
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