Radiation is used to describe any form of any originating from a source.
Intensity = power of incident radiation/area I = P divided by A
With power (in Watts) and Area (in metres squared), Intensity is measured in Watts per metre squared.
The intensity of radiation will decrease with distance from a source and/or with the nature of the medium through which it is being transmitted:
Light hitting an area will have intensity (in Watts per metre squared).
Light travelling twice as far will spread covering twice the width and twice the height.
This is 4 times the original area and so the intensity is ¼ the…