Kinetic energy (KE)

All moving objects have kinetic energy (KE). The KE an object has depends on its:

  • mass
  • speed

Calculating kinetic energy

Here is the equation for calculating kinetic energy:

KE = ½ mv2

or

KE = ½ × m × v2

where:

KE is the kinetic energy in joules, J

m is the mass in kilograms, kg

v is the speed in metres per second, m/s

For example, what is the kinetic energy of a 1000 kg car travelling at 5 m/s?

KE = ½ × 1000 × 25 = 500 × 25 = 12500 J