Calculating Efficiency of Simple Machines

Efficiency is a measure of how much more work must be put into a machine than you get out of the machine. In the real world, the efficiency of a machinewill always be less than 100%. This means that a machine will never do work for you. The best you can hope for in real life is that you do not have to put much more work into a machine than you get out. If there was no friction, the best you could hope for is an efficiency of 100% meaning work in = work out. We can calculate efficiency by comparing work out to work in.Look below for an example.

Efficiency = Work input / Work output x 100%

or we can calculate effiency by comparing TMA to AMA. Look below for an example.

Efficiency = AMA / TMA x 100%

Look Here for Practice Problems: Simple Machines Problem Set