A technique to teach bimanual robots stir-fry cooking

As robots make their way into a variety of real-world environments, roboticists are trying to ensure that they can efficiently complete a growing number of tasks. For robots that are designed to assist humans in their homes, ...


A pocket cooling device based on a cascade mechanism

Recent technological advances have enabled the development of increasingly compact and flexible devices. This includes wearable or portable technology, such as smart watches, earphones or other smart accessories, which can ...

Energy & Green Tech

Study finds heat pumps more efficient than gas or oil

As the year 2030 approaches, governments and industry leaders are actively studying ways to meet a European climate law aiming to reduce greenhouse gas emissions by at least 55%. The European Green Deal initiative has set ...

Energy & Green Tech

New smart-roof coating enables year-round energy savings

Scientists have developed an all-season smart-roof coating that keeps homes warm during the winter and cool during the summer—without consuming natural gas or electricity. Research findings reported in the Dec. 17 edition ...


New engine capability accelerates advanced vehicle research

In the quest for advanced vehicles with higher energy efficiency and ultra-low emissions, Oak Ridge National Laboratory researchers are accelerating a research engine that gives scientists and engineers an unprecedented view ...

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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.

This text uses material from Wikipedia, licensed under CC BY-SA