An electromagnetic wave with a peak magnetic field component of 3.2 × 10−⁷ T carries what average power per unit area? (μ₀ = 4π × 10−⁷ T⋅m/A,ε₀ = 8.85 × 10−¹² C²/N⋅m²,and c = 3.00 × 10⁸ m/s) A) 12 W/m² B) 3.0 W/m² C) 2.7 W/m² D) 1.3 W/m²

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Quizplus · Accepted Answer

The average power per unit area carried by an electromagnetic wave is given by:$$P_{avg} = \frac{1}{2}ε_0 c B_{max}^2$$where:* ε_0 is the permittivity of free space* c is the speed of light* B_{max} is the peak magnetic field componentPlugging in the given values, we get:$$P_{avg} = \frac{1}{2}(8.85 × 10^{-12} C^2/N⋅m^2)(3.00 × 10^8 m/s)(3.2 × 10^{-7} T)^2 = 12 W/m^2$$Therefore, the average power per unit area carried by the electromagnetic wave is 12 W/m^2.

An Electromagnetic Wave with a Peak Magnetic Field Component of 3.2