An electromagnetic wave with a peak magnetic field component of 3.2 *10 ^- ⁷ T carries what average power per unit area? ($\mu$₀ = 4$\pi$ * 10^-⁷T.m/A, $\varepsilon$₀ = 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 is given by:$$S = \frac{1}{2}c\varepsilon_0 E_0^2$$where:* S is the average power per unit area* c is the speed of light* $\varepsilon_0$ is the permittivity of free space* $E_0$ is the peak electric field componentWe can find $E_0$ from the peak magnetic field component using the following equation:$$E_0 = cB_0$$where:* $B_0$ is the peak magnetic field componentSubstituting this into the equation for S, we get:$$S = \frac{1}{2}c\varepsilon_0 c^2B_0^2$$Plugging in the given values, we get:$$S = \frac{1}{2}(3.00 	imes 10^8 	ext{ m/s})(8.85 	imes 10^{-12} 	ext{ C}^2/	ext{Nm}^2)(3.2 	imes 10^{-7} 	ext{ T})^2$$$$S = 12 	ext{ W/m}^2$$Therefore, the correct answer is A.

An Electromagnetic Wave with a Peak Magnetic Field Component of 3.2