Question

How Does Radiation Transfer Heat Energy?

Answer 1

Hint:Radiation is the transfer of Energy (heat Energy) from one object at higher temperature to another object at lower temperature without being in Physically contact with each other. Unlike Convection and Conduction, Radiation does not need any medium to transfer heat energy. It can even take place in vacuum.

Complete answer:
Radiation transfers heat through Photons and hence it does not have any medium to transfer heat from one place to another. Transfer of heat through Radiation can be done through any medium or even through vacuum but, Transfer of heat through radiation is more effective in case of vacuum as there are no other particles or surfaces to absorb the heat energy. In case of Air the heat gets slightly absorbed by particles in air (gas particles, dust particles etc.) and due to this the efficiency of radiation gets decreased.
Thermal radiations or Heat radiations are produced due to the interatomic Collision of charged particles and these particles then radiate heat in form of photons. These photos travel in any medium or in vacuum in the form of electromagnetic waves and transfer the heat energy to the surface on which they fall.
One more advantage of Thermal Radiation is that it can be made to focus on an object just like a light wave, and hence we can use thermal radiation more effectively by focusing on the area where it is required. While in case of convection and conduction it is not possible to concentrate it on one place.

Note:
The best Example of Thermal Radiation is the energy that we receive from the Sun. Sun is a major source of energy for earth and it sends heat energy from its surface to earth through thermal radiations which travels through vacuum and reaches earth without facing much loss in such a large distance. Thermal Radiations come to us in the form of light, but that light is not visible to our naked eye. It comes in the form of Infrared Radiation and most of the light that comes from sun to earth gets reflected back into space and we only receive a few amounts of it.