Heat as we all know is a form of energy that flows from a region of high temperature to a region of low temperature. The various forms by heat transfer take place is Conduction, Convection, and Radiation.
The transfer of the heating mechanism can be better understood by simple examples below.
The passing of the book from one corner to another by the passing the book to from hands of one student to another is an example of conduction, The atoms a solid crystal vibrates on there mean position and pass the energy from atom to another.
The convection can be defined as the energy that flows in the form of currents in the fluid medium. The space just above the flame of a candle appears to be moving ( If you have ever observed ) .this is because the air just above the flame becomes hot and rises up and the cold air rushes to takes its place, this the example of convection heat transfer which changes the density of the air above.
The transfer of heat energy in the absence of any medium is known as Radiation, heat transfer in a vacuum is done by radiation only. It can also be understood by an example as the rays of the sun reaches earth through Vacuum.
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