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Mechanical advantage

In physics and engineering mechanical advantage (MA) is the factor by which a machine multiplies the force put into it. The mechanical advantage can be calculated for the following simple machines by using the following formulas:

Most generally, the mechanical advantage is calculated thus:

also, the Force exerted IN to the machine × the distance moved IN will always be equal to the force exerted OUT of the machine × the distance moved OUT. For example; using a block and tackle with 6 ropes, and a 600 pound load, the operator would be required to pull the rope 6 feet, and exert 100 pounds of force to lift the load 1 foot, therefore:

or more basic, WORKin = WORKout

This requires an ideal simple machine, meaning that there are no losses due to friction or elasticity. If friction or elasticity exist in the system efficiency will be lower; Workin will be greater than Workout

Mechanical advantage also applies to torque. A simple gearset is able to multiply torque.

There are two types of mechanical advantage:

  1. Ideal mechanical advantage (IMA)
  2. Actual mechanical advantage (AMA)