energij
Energij is a physical quantity that describes the capacity to do work or to produce heat. In physics it is treated as a scalar quantity, though its exact meaning depends on the context. Energy can exist in many forms and can be stored, transferred, or transformed between forms without changing the total amount in a closed system.
Common forms include kinetic energy (motion), potential energy (position in a field), thermal energy (random molecular
Energy is conserved in isolated systems, meaning it can change form but the total amount remains constant.
Energy sources are categorized as primary sources, such as fossil fuels, sunlight, wind, or uranium, which are
In everyday use, energy also describes dietary energy in humans and animals, typically expressed in kilocalories.