Cieplo

Cieplo (Polish for heat or warmth) is a form of energy transfer driven by a difference in temperature between bodies or systems. In physics, heat is energy in transit, while temperature describes the average kinetic energy of particles in a substance. Heat can move via conduction, convection, or radiation, and can cause phase changes, leading to latent heat.

Heat is measured in joules in the SI system; common practical units include calories, kilowatt-hours, and British thermal units. The amount of heat required to raise a substance's temperature depends on its mass and specific heat capacity. Calorimetry is used to quantify heat exchange in experiments.

Natural sources include solar radiation and geothermal heat; human-made sources include burning fuels, electrical heating, heat pumps, and district heating networks. Heat is used for space heating, water heating, cooking, industrial processes, and energy storage. Energy efficiency practices—insulation, airtightness, and efficient heating systems—are central to reducing energy consumption and emissions.

In thermodynamics, the first law describes energy conservation, stating that heat added to a system changes its internal energy. The second law introduces entropy and the direction of natural heat flow from hotter to colder bodies. Practical engineering addresses heat transfer rates, thermal resistance, and regenerative technologies.

Notes: In Polish, cieplo (with the diacritic: ciepło) denotes heat or warmth; it is commonly used in everyday language and scientific contexts to refer to thermal energy and domestic heating.