Kinetic & Potential Energy Calculator

Two forms of mechanical energy, added together

A 2 kg object moving at 10 m/s and positioned 5 meters high (with standard gravity, g = 9.81 m/s²) has kinetic energy of 100.00 J and potential energy of 98.10 J, for a total mechanical energy of 198.10 J.

Kinetic energy (KE = 1/2 x m x v² = 0.5 x 2 x 10² = 0.5 x 2 x 100 = 100) depends on the square of velocity, not velocity directly -- doubling speed quadruples kinetic energy, which is why higher speeds carry disproportionately more energy (and more damage potential in a collision) than a simple doubling might suggest.

Potential energy (PE = m x g x h = 2 x 9.81 x 5 = 98.10) scales directly and linearly with height -- unlike kinetic energy's squared relationship with velocity, doubling height simply doubles potential energy, a much more predictable, proportional relationship.

Why these two energies are often calculated together

Joules if m is kg, v is m/s, and h is meters. This pairing reflects a core physics principle -- in an idealized system without friction or air resistance, total mechanical energy (KE + PE) stays constant as an object trades height for speed or vice versa, like a pendulum swinging or a ball rolling down a hill, converting potential energy into kinetic energy as it falls.

The result is in joules specifically because the inputs are in the matching SI units (kilograms, meters per second, meters) -- using different unit systems for mass, velocity, or height would require converting to these SI units first, or the resulting joule figure wouldn't be accurate.

Standard gravity (9.81 m/s²) is Earth's average gravitational acceleration at sea level -- this value would need to change for a calculation on a different planet or celestial body, or for extreme-precision work accounting for gravity's small variation by latitude and altitude on Earth itself.

Related physics tools

For the force and acceleration relationship that produces the velocity used in this kinetic energy calculation, the Force, Mass & Acceleration Calculator is the related upstream tool.

For converting this energy result into a different energy unit (like calories or BTU) rather than staying in joules, the Energy Unit Converter handles that conversion.

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