Kinetic energy
In physics, the kinetic energy (KE) of an object is the energy that it has due to its motion
Half life
The radioactivity of a sample decreases over time. Half life is a measurement of this decrease
Gravitational potential energy
Lifting an object in a gravitational field transfers energy into the objects gravitational energy store
Efficiency
The efficiency of a device is the proportion of input energy that is converted to useful energy