The intensity of a plane electromagnetic wave with B₀ = 1.0×10⁻⁴ T is W m⁻². (c = 3×10⁸ m s⁻¹, μ₀ = 4π×10⁻⁷ N A⁻²)

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(1) 1.19×10⁶. Given: B₀ = 1.0×10⁻⁴ T, c = 3×10⁸ m s⁻¹, μ₀ = 4π×10⁻⁷ N A⁻². Idea: intensity is the time-averaged energy crossing unit area per second. For a plane wave I = 1/2(cB₀²)/(μ₀), where the 1/2 is the average of sin²(ω t - kx) over a cycle. Numerator: cB₀² = (3×10⁸)(1.0×10⁻⁴)² = 3 in SI units. Denominator: 2μ₀ = 2×4π×10⁻⁷ = 2.513×10⁻⁶. I = 3/(2.513×10⁻⁶) = 1.19×10⁶ W m⁻².

The intensity of a plane electromagnetic wave with B₀ = 1.0×10⁻⁴ T is ______ W m⁻². (c = 3×10⁸ m s⁻¹, μ₀ = 4π×10⁻⁷ N A⁻²)

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