The Power of Light: Calculating the Electric Field Amplitude

What is the amplitude of the electric field for the light that is produced by the projector?

A projector is illuminating a screen that is 2.00 m tall and 3.00 m wide. The power of the projector is 265 W.

A. 29.4 V/m

B. 182 V/m

C. 4.26 V/m

D. 129 V/m

Answer:

The amplitude of the electric field for the light produced by the projector is approximately 4.26 V/m.

To calculate the amplitude of the electric field for the light produced by the projector, we can use the formula:

Power = (Electric Field Amplitude)^2 * (Speed of Light)^2 * (Area)

Given that the power of the projector is 265 W and the dimensions of the screen are 2.00 m tall and 3.00 m wide, we can substitute these values into the formula:

265 W = (Electric Field Amplitude)^2 * (3.00 x 10^8 m/s)^2 * (2.00 m x 3.00 m)

Now, we can solve for the electric field amplitude:

(Electric Field Amplitude)^2 = 265 W / [(3.00 x 10^8 m/s)^2 * (2.00 m x 3.00 m)]

(Electric Field Amplitude)^2 = 265 W / (9.00 x 10^16 m^2/s^2)

Electric Field Amplitude = sqrt(265 W / (9.00 x 10^16 m^2/s^2))

Calculating this value gives us the amplitude of the electric field for the light produced by the projector.

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