Velocity Ratio (VR): It is ratio of distance moved per unit time by effort to the distance moved per unit time by load.
, where y is distance moved by the effort (P), and x is distance moved by the load (W).
Mechanical Advantage (MA): It is ratio of load lifted and effort applied on a lifting machine. Its significance is that how many times of effort, the load is lifted.
, where W is load lifted in Newton, and P is effort applied in Newton.
Efficiency of Lifting Machine, η: Efficiency of lifting machine is the ratio of work done by the machine to lift the load and work done on the machine. It is simply ratio of output and input.
Ideal Machine: It is a hypothetical machine that has 100% efficiency which is practically not possible. It is also known as frictionless machine or perfect machine.
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