If the intensity of an electromagnetic wave is 80 MW/m², what is the amplitude of the magnetic field of this wave? (c = 3.0 x 10⁸ m/s, μ₀ = 4π × 10^-7 T ∙ m/A, ε₀ = 8.85 × 10^-12 C²/N ∙ m²) A) 0.82 mT B) 0.33 µT C) 10 T D) 14 T E) 0.58 mT

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Quizplus · Accepted Answer

The intensity of an electromagnetic wave is given by:$$I = \frac{1}{2} c \varepsilon_0 E_0^2 = \frac{1}{2} c \mu_0 H_0^2$$where I is the intensity, c is the speed of light, ε0 is the permittivity of free space, E0 is the amplitude of the electric field, μ0 is the permeability of free space, and H0 is the amplitude of the magnetic field.Solving for H0, we get:$$H_0 = \sqrt{\frac{2I}{\mu_0 c}}$$Plugging in the given values, we get:$$H_0 = \sqrt{\frac{2(80 	imes 10^6 	ext{ W/m}^2)}{4\pi 	imes 10^{-7} 	ext{ T} \cdot 	ext{m/A} 	imes 3.0 	imes 10^8 	ext{ m/s}}} = 0.82 	ext{ mT}$$

If the Intensity of an Electromagnetic Wave Is 80 MW/m2

If the Intensity of an Electromagnetic Wave Is 80 MW/m²