what is the difference between conduction, convection and radiation?
All three are processes of heat transfer through either a solid, liquid or a gaseous medium.
Conduction is a process of heat transfer which occurs only in solids and is quite an efficient mechanism. It requires the transfer of energy in the form of heat by successive collisions of molecules of a solid. No mass movement takes place.
Convection is a process of heat transfer which occurs either in liquids or gases. In this process energy in the form of heat is transferred with the help of mass movement of energetic molecules from one point to another.
Radiation is a process of heat transfer which occurs mainly through a vacuum or a gaseous medium. In this mechanism electromagnetic waves carry energy from a hot body as it spread throughout a media.
conduction:- It is a process of transfer of heat which takes place only in solids. Heat can be passed through conductors eg. all metals
convection:- It is a process of transfer of heat which takes place in liquids and gasses.
radiation:- Radiation is a process in which no medium is used for heat transfer. Eg.radiation transfered from sun to earth. As we know that there is nothing between sun and earth exept vacuum so no medium is required for heat transfer for radiation