Field intensity: An electromagnetic wave has a peak electric field of 3.0 kV/m. What is the intensity of the wave? (c = 3.0 × 10⁸ m/s, μ₀ = 4π × 10^-7 T ∙ 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

Question

Quizplus · Accepted Answer

The intensity of an electromagnetic wave is given by I = (1/2)cεE^2, where c is the speed of light, ε is the permittivity of free space, and E is the peak electric field. Plugging in the given values, we get I = (1/2)(3.0×10^8)(8.85×10^-12)(3.0×10^3)^2 = 12 kW/m^2. Therefore, the answer is choice B.

Field Intensity: an Electromagnetic Wave Has a Peak Electric Field