Question

what is radiation ? give two examples

Answer 1

Radiation is the transfer of energy without the involvement of any medium.       Eg.-1>Radiation of heat and light energy from Sun
       2> Radiation from Radioactive substances

Answer 2

Radiation is the process of transfer of heat without any medium. So, it can be observed even in vacuum.
EXAMPLES:-
1) Process of rays of sun reaching the earth
2) Ultraviolet radiation