Kilojoule

Kilojoule (kJ) is a unit of energy in the International System of Units (SI). It is equal to 1000 joules, the standard unit of energy in the SI system. The kilojoule is commonly used in scientific and engineering contexts, as well as in everyday life to measure the energy content of food.

Definition

The kilojoule is defined as the amount of energy transferred when a force of one newton moves an object one meter against the force. This definition is based on the principle of work in physics, where work is the transfer of energy.

Usage

In scientific and engineering contexts, the kilojoule is used to measure energy in various forms, including kinetic energy, potential energy, thermal energy, and chemical energy. It is also used to measure heat and electricity.

In everyday life, the kilojoule is most commonly used to measure the energy content of food. In many countries, food packaging includes information on the energy content of the food in kilojoules. This allows consumers to compare the energy content of different foods and make informed choices about their diet.

Conversion

One kilojoule is equal to 1000 joules. It can also be converted to other units of energy. For example, one kilojoule is approximately equal to 0.239 calories, 0.948 British thermal units, and 0.0002778 kilowatt hours.

See also

• Energy (physics)
• Joule
• Calorie
• British thermal unit
• Kilowatt hour