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A traveling electromagnetic wave in a vacuum has an electric field amplitude of 72.7 V/m. Calculate the intersity S of this wave. Then, determine the amount of energy U that flows through area of 0.0263 m² over an interval of 19.7 s, assuming that the area is perpendicular to the direction of wave propagation.

S = ...
U = ...

User Walmik
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The intensity of the electromagnetic wave is 605.95 W/m^2 and the energy flowing through the area is 303.48 J.

To calculate the intensity of an electromagnetic wave, we can use the formula:

I = (E0)2 / (2ρ)

where I is the intensity, E0 is the electric field amplitude, and ρ is the impedance of free space (~377 Ω).

Given that the electric field amplitude is 72.7 V/m, we can substitute this value into the formula:

I = (72.7)2 / (2 × 377)

Solving this equation gives us the intensity: I = 605.95 W/m2

To calculate the amount of energy flowing through an area, we can use the formula:

U = I × A × t

where U is the energy, I is the intensity, A is the area, and t is the time interval.

Substituting the given values of I = 605.95 W/m2, A = 0.0263 m2, and t = 19.7 s into the formula:

U = 605.95 × 0.0263 × 19.7

Solving this equation gives us the energy: U = 303.48 J

User MBach
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