A monochromatic point like light source emits 1.50 W of electromagnetic power uniformly in all directions.How far from the point source is the Poynting vector 0.367 W/m²?

Question

Quizplus · Accepted Answer

We can use the formula for the magnitude of the Poynting vector at a distance r from a point source:

|S| = P/(4πr^2)

where P is the electromagnetic power emitted by the source.

Plugging in the given values, we get:

0.367 W/m^2 = 1.50 W/(4πr^2)

Solving for r, we get:

r = √(1.50 W/(4π*0.367 W/m^2)) = 0.57 m

Therefore, the answer is (D) 0.57 m.

A Monochromatic Point Like Light Source Emits 1