energiának

Energy is a physical quantity that describes the capacity to perform work or produce changes in systems. In physics, energy can be stored, transferred, or transformed from one form to another, and the total amount in an isolated system is conserved.

Common forms include kinetic energy, potential energy, thermal energy, chemical energy, electrical energy, radiant energy, and nuclear energy. Sound energy is often considered a mechanical form associated with motion and pressure waves.

Energy is measured in joules (J) in the International System of Units, with larger scales such as kilojoules, megajoules, or kilowatt-hours used in practice (1 kilowatt-hour equals 3.6 million joules). Power is the rate of energy transfer, measured in watts (W).

Energy can be transferred by doing work or by heat transfer. Efficiency describes how much input energy becomes useful output, with losses to non-useful forms such as waste heat. Systems often aim to maximize efficiency and minimize environmental impact.

Humans obtain energy primarily from chemical energy stored in fuels (fossil fuels and biofuels) and from renewable sources such as solar, wind, hydro, geothermal, and biomass. The choice of energy mix affects climate, air quality, and economic stability.

In Hungarian, energiának is the dative singular form of energia and is used in phrases meaning "for energy" or "to energy."