Joule
The SI unit of work is newton-meter.
Work
Any time you exert a force on an object to move some distance.
Power
The rate at which work is done.
Watt
When work is measured in joules and time in seconds, the SI unit of power is the Joule per second.
Machine
Devices that allow you to do work in an easier way.
Input force
When you do work, the force you exert.
Output force
The force excreted on an object by a machine.
Mechanical advantage
The number of times a machine increases a force exerted on it.
Efficiency
A machine compares output work to input work.
Simple machine
The most basic