Explain the concept of intensity of electromagnetic waves.

Explanation

The energy crossing per unit area per unit time and perpendicular to the direction of propagation of electromagnetic wave is called the intensity.
Instensity, I = `[mu] ` c or
`I = ("total electromagnetic energy (U)")/("Surface area" (A) xx "time" (t))`
= `("Power (P)")/( "Surface area"(A))`