Kinetic Energy Calculator
Calculate classical translational kinetic energy in joules from object mass in kilograms and velocity in metres per second.
Calculate translational kinetic energy
How this tool works
Classical kinetic energy depends linearly on mass but quadratically on speed. The calculator uses SI units and accepts signed velocity because direction changes momentum but not the energy associated with speed.
Translational kinetic energy KE equals one half multiplied by mass m and velocity squared v². Kilograms and metres per second produce joules.
How to use it
- Enter positive mass in kilograms.
- Enter velocity in metres per second.
- Read kinetic energy and note the squared influence of velocity.
Worked examples
Moving object
- Input
- 10 kg at 5 m/s
- Output
- 125 J
Velocity squared is 25. Multiplying by ten kilograms and one half gives 125 joules of translational kinetic energy.
Double velocity
- Input
- 10 kg at 10 m/s
- Output
- 500 J
Doubling velocity from five to ten makes its square four times larger, so energy rises from 125 to 500 joules.
Limitations
- The classical formula is not suitable near relativistic speeds.
- Rotation, deformation, friction, and other energy forms are excluded.