Heat transfer is all about the transfer of heat from one point to another. If we consider any system which will be at higher temperature compared to surroundings, there will be transfer of heat from system to the surroundings.
Heat transfer is given by
Where,m is the mass,
C is the specific heat and
$\Delta$ T is the temperature difference in K.
There are three types of Heat transfer
Heat transfer (Q) by Conduction formula is given by
Where, k is the thermal conductivity of the material,
A is the cross sectional area,
is the higher temperature,
is the cooler temperature,
t is the time taken,
d is the thickness of the material.
Heat transfer by Convection is given by
is the heat transfer coefficient,
The Heat transfer by radiation is given by
Here $\sigma$ is the Stefan Boltzmann Constant.
Heat transfer is usually expressed in Joules. Heat transfer formula is used in problems to find the heat transfer taking place for any given material.