Energy & Power Calculator

What this does

An energy & power calculator works out the kinetic energy and gravitational potential energy of a mass, their total, and the average power if that energy is delivered over a given time.

How to use it

1. Enter the mass in kilograms.
2. Enter the velocity (m/s) and height (m).
3. Optionally enter a time in seconds for the power.
4. Read the energies in joules and the power in watts.

How it works

Power is energy per unit time, so a 100 W device for an hour uses 100 Wh. Kinetic energy depends on speed squared; potential energy near Earth on height.

P = E ÷ t; KE = ½mv²; PE = mgh

Understanding your result

The distinction to hold onto is that power is the rate and energy is the total: a high-wattage device is only expensive if it runs long enough to rack up energy. Kinetic energy scales with speed squared, so doubling speed quadruples the energy, which is why impacts and braking distances grow so sharply, and potential energy near Earth depends only on height and mass.

Example

A 2 kg mass moving at 3 m/s, 5 m up, has 9 J of kinetic and about 98.1 J of potential energy; delivering that 107 J over 10 s averages about 10.7 W.