The rate of energy flow per unit area of an electromagnetic wave has an average value of 0.695 W/m².The wave is incident at right angles upon a rectangular area measuring 1.5 m by 2.0 m.How much total energy falls upon this rectangle each minute? (ε₀ = 8.85 × 10^-12 C²/N ∙ m²,μ₀ = 4π × 10^-7 T ∙ m/A,c = 3.0 × 10⁸ m/s) A)130 J B)160 J C)190 J D)220 J E)250 J

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Quizplus · Accepted Answer

The average rate of energy flow per unit area is given by:$$S = \frac{1}{2} c \epsilon_0 E_0^2$$where c is the speed of light, $\epsilon_0$ is the permittivity of free space, and $E_0$ is the amplitude of the electric field.The total energy falling upon the rectangle each minute is given by:$$E = SAt$$where A is the area of the rectangle and t is the time.Substituting the given values into these equations, we get:$$S = \frac{1}{2} (3.0 	imes 10^8 	ext{ m/s})(8.85 	imes 10^{-12} 	ext{ C}^2/	ext{N} \cdot 	ext{m}^2)(0.695 	ext{ W/m}^2) = 0.381 	ext{ W/m}^2$$$$E = (0.381 	ext{ W/m}^2)(1.5 	ext{ m})(2.0 	ext{ m})(60 	ext{ s}) = 136.8 	ext{ J}$$Therefore, the correct answer is A.

The Rate of Energy Flow Per Unit Area of an Electromagnetic