Related topics: electricity

A cold-health watch and warning system for cold waves in Quebec

A team from the Institut national de la recherche scientifique (INRS) and the Institut national de santé publique du Québec (INSPQ), led by Professor Fateh Chebana, has recently developed a cold-health watch and warning ...

Japan spacecraft carrying asteroid soil samples nears home

A Japanese spacecraft is nearing Earth after a yearlong journey home from a distant asteroid with soil samples and data that could provide clues to the origins of the solar system, a space agency official said Friday.

In a warming climate, can birds take the heat?

We don't know precisely how hot things will get as climate change marches on, but there's reason to believe animals in the tropics may not fare as well as their temperate relatives. Many scientists think tropical animals, ...

Applying environmental genomics to coral conservation

Oceans are a bellwether for the planet's health, absorbing over 90% of the sun's energy. They demonstrate the extent to which rising temperatures are threatening coral reefs and other vital ecosystems that support biodiversity. ...

Researchers decode thermal conductivity with light

Groundbreaking science is often the result of true collaboration, with researchers in a variety of fields, viewpoints and experiences coming together in a unique way. One such effort by Clemson University researchers has ...

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Heat

In physics and thermodynamics, heat is the process of energy transfer from one body or system to another due to a difference in temperature. In thermodynamics, the quantity TdS is used as a representative measure of the (inexact) heat differential δQ, which is the absolute temperature of an object multiplied by the differential quantity of a system's entropy measured at the boundary of the object.

A related term is thermal energy, loosely defined as the energy of a body that increases with its temperature. Heat is also loosely referred to as thermal energy, although many definitions require this thermal energy to actually be in the process of movement between one body and another to be technically called heat (otherwise, many sources prefer to continue to refer to the static quantity as "thermal energy"). Heat is also known as "Energy".

Energy transfer by heat can occur between objects by radiation, conduction and convection. Temperature is used as a measure of the internal energy or enthalpy, that is the level of elementary motion giving rise to heat transfer. Energy can only be transferred by heat between objects - or areas within an object - with different temperatures (as given by the zeroth law of thermodynamics). This transfer happens spontaneously only in the direction of the colder body (as per the second law of thermodynamics). The transfer of energy by heat from one object to another object with an equal or higher temperature can happen only with the aid of a heat pump, which does work.

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