The Force Ratio or Mechanical Advantage.

The force ratio , also known as Mechanical Advantage, M.A  of a machine is the ratio of the  Load to the Effort.

VELOCITY RATIO

The velocity ratio  V.R  of  a machine is defined as the ratio of the distance moved by the effort to the distance moved by the load.

The mechanical advantage of a machine  depends on the friction. If friction is present, more effort will be required to move part of the machine.

From the expression

The smaller the friction, the smaller the effort that will be used and the larger the M.A

V.R  is independent of friction, it depends on  distance move by load and distance move by effort.

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