There are three modes of heat transfer :
1. conduction.
2. convection,
3. radiation.
1. Conduction.
It is that method of heat transfer in which heat is transmitted from the hotter end to the colder end of the object without the actual movement of the heated partilces. Solids are heated by this method.
2. Convection.
It is the process of heat transfer due to the actual movement of the heated particles of liquid or gas. Liquids and gases are heated by this method.
3. Radiation.
It is the process in which heat is transmitted directly from the our ce of heat or hot object to a cold object without medium in between them. In other words no medium is required for heat radiation
