Actual mechanical advantage (AMA) is the output force of a machine divided by the input force applied to the machine.

Here's the formula:

AMA = Output Force / Input Force

It's important to understand that AMA takes into account any energy losses due to friction and other inefficiencies within the machine.

For example:

If you apply a force of 10 Newtons (input force) to a lever and it lifts a 20 Newton weight (output force), then the AMA is:

AMA = 20 N / 10 N = 2

This means the lever amplifies your input force by a factor of 2, even though some energy was lost due to friction.