a temperature difference and the presence of electromagnetic waves
Explanation:
For radiations to occur, there must be presence of temperature difference and electromagnetic waves.
Radiation is a form of heat transfer that does not require a medium. Any hot body emits radiation from its surface.
A hot body is not at thermal equilibrium with its environment.
It has some of its electrons in excited state and by so they emit radiations.
Electromagnetic waves that vibrates transversely emits radiations. This is the mode of heat transfer in place for most electromagnetic waves
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Electromagnetic radiation brainly.com/question/6818046
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