explain the principle of heat exchange
Answers
Heat is transferred to and from objects -- such as you and your home -- via three processes: conduction, radiation, and convection. Conduction is heat traveling through a solid material. Radiation is heat traveling in the form of visible and non-visible light. Convection is another means for the heat from your walls and ceiling to reach you.
Answer:
In 172, Pierre Prevost put forward a theory of
exchange of heat. According to this theory, all
bodies at all temperatures above the absolute zero
temperature (0 K) radiate thermal energy to the
surroundings and at the same time receive radiant
energy from the surróundings. Thus, there is
continuous exchange of radiant energy between a
body and its surroundings.
The quantity of radiant enersy (thermal energy)
emitted bya body per unit time depends upon the
naure of the emitting surtace, the area of the
surface and the temperature of he surface. The
quantity of radiant energy absorbed by a body per
unit time depends upon the nature of the absorbing
surface, the area of the surface and the time rate at
which the radiant energy is incident on the body.
If the time rate of emission of thermal energy is
greater than the time rate ot absorption of thermal
energy, the temperature of the body falls. If the
emission rate is less than the absorption rate, the
temperature of the body increases. If the emission
rate equals the absorption rate, the temperature of
the boay remains constant.
INote : A body appearS red if its temperature is around
800,and white hot if its temperature 1s around
3000 C)