This standard energy metric quantifies large amounts of mechanical work, heat, or electrical energy. It is roughly equivalent to the kinetic energy of a one-tonne vehicle moving at 160 kilometres per hour. Engineers use it to rate heavy machinery, explosive yields, and large-scale heating systems.
Heard on the job
The regenerative braking system captures about three megajoules of energy per stop.
Also heard as
- MJ
Related terms
Gigajoule
A metric unit of energy equivalent to one billion joules, often used for billing natural gas.
kilojoule
An SI unit of energy, work, or heat equal to 1,000 joules.
Exajoule
A metric unit of energy equal to one quintillion joules.
nanojoule
A nanojoule is one billionth of a joule, the standard SI unit for very small amounts of energy.