Heat transfer is the transition of thermal energy from a hotter mass to a cooler mass. When an object is at a different temperature than its surroundings or another object, transfer of thermal energy, also known as heat transfer, or heat exchange, occurs in such a way that the body and the surroundings reach thermal equilibrium; this means that they are at the same temperature. Heat transfer always occurs from a higher-temperature object to a cooler-temperature one as described by the second law of thermodynamics or the Clausius statement.
Convection heat transfer is the transfer of heat by the movement of a fluid.
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Convection - heat transfer through liquids.Conduction - heat transfer through solids.Radiation - heat transfer through vacuum.
Gas is used to heat transfer the sun, and which can make a thing called solar energy.
For conductive and convective heat transfer, the rate of heat transfer is proportional to the the temperature difference; if you double the difference you will double the rate of heat transfer. For radiative heat transfer, the rate of heat transfer is proportional to the difference of the 4th powers of the absolute temperatures.
Convection heat transfer is the transfer of heat by the movement of a fluid.
The transfer of heat by fluid is convection.
Thermal energy
They're both modes of heat transfer via material media.
convection
There is a special mechanism that controls heat transfer.