Question

a projector is producing electromagnetic radiation. when the radiation hits a screen with an area of 2.0 m by 3.0 m it has a with an electric field with an amplitude of 1.50 x 102 v/m . what is the power of the projector?

Answer 1

To calculate the power of the projector, use the formula P = E^2 / (2Z), where P is the power, E is the amplitude of the electric field, and Z is the impedance of free space. The power of the projector is 179.1 W.

Step-by-step explanation:

To calculate the power of the projector, we need to use the formula P = E^2 / (2Z), where P is the power, E is the amplitude of the electric field, and Z is the impedance of free space (approximately 377 ohms). First, we need to calculate the intensity (I) of the electromagnetic radiation, which is equal to (E^2) / (2Z). Then, we can calculate the power by multiplying the intensity by the area of the screen.

Given that the electric field amplitude is 1.50 x 10^2 V/m, the impedance of free space is approximately 377 ohms, and the screen has an area of 2.0 m by 3.0 m, we can calculate:

1. Intensity = (1.50 x 10^2)^2 / (2 * 377) = 22500 / 754 = 29.85 W/m^2
2. Power = Intensity * Area = 29.85 * (2.0 * 3.0) = 179.1 W