A cell phone transmits 2.0 W of power at 380 MHz in a spherical pattern.What is the intensity of the radiation at the cell tower,located 3.0 km away?

Question

Quizplus · Accepted Answer

The intensity of radiation at a distance r from a spherical transmitter with power P is given by:

I = P/4πr^2

Here, P = 2.0 W and r = 3.0 km = 3000 m.

Substituting these values, we get:

I = 2.0/(4π(3000^2))

I ≈ 1.8 × 10^-8 W/m^2

Option B is the closest value to this result.

A Cell Phone Transmits 2