What units is kinetic energy measured in?

Kinetic energy is measured in joules (J) in the SI system. Large values may be expressed in kilojoules (kJ) or megajoules (MJ).

Why does doubling speed quadruple kinetic energy?

Because velocity is squared in KE = ½mv². If v doubles, v² quadruples, so KE quadruples.

Kinetic energy is a scalar — it has magnitude but no direction.

Proper Time (Δt) s

Velocity (v) fraction of c

Enter mass and velocity above

Convert mass to kg and velocity to m/s using the selected units.

Apply the formula: KE = ½ × m × v²

Result is in joules (J). Divide by 1000 for kilojoules.

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