Question

What do you mean by transfer of heat? Explain the process of transfer of heat in solids, liquids and gases.

Answer 1

Flow of heat from one object to another whether solid or liquid is called transfer of heat. Heat always flows from a body at higher temperature to another body at lower temperature. In other words, heat always flows from a hotter body to a colder body. In this process, the temperature of the hot body falls as it releases heat which is received by the colder body or the body having lower temperature. Thus the temperature of the colder body or less hotter body rises. The flow of heat stops when temperature of both the bodies becomes equal.
Transfer of heat takes place through conduction, convection and radiation.
Conduction is the process of transfer of heat from one particle to the next particle in a solid without the particles actually moving from their position.
Convection is the process of heat transfer in which the particles change their positions by constantly moving from the hotter region to the cooler region, thus causing heat energy to flow. In convection heat travels through the liquids and gases.
Radiation is the process in which heat is transferred from one body to another body without involving the molecules of the medium. Heat transfer through radiation does not depend on the medium.