An electromagnetic wave has a peak electric field of 3.0 kV/m. What is the intensity of the wave? (c = 3.0 x 10⁸ m/s, μ₀ = 4π × 10^-7T ∙ m/A, ε₀ = 8.85 × 10^-12 C²/N ∙ m²) A) 24 kW/m² B) 12 kW/m² C) 8.0 kW/m² D) 4.0 kW/m²

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Quizplus · Accepted Answer

The formula for intensity is I = cε0/2 * E0^2, where c is the speed of light, ε0 is the permittivity of free space, and E0 is the peak electric field. Plugging in the given values, we get I = (3.0 x 10^8 m/s)(8.85 x 10^-12 C^2/Nm^2)/(2) * (3.0 x 10^3 V/m)^2 = 12 kW/m^2. Therefore, the best choice is B.

An Electromagnetic Wave Has a Peak Electric Field of 3