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A human body of total surface area 1.6 m² radiates as an ideal black body. Taking body temperature 37 degC and Stefan constant sigma = 6.0 * 10⁻⁸ W/(m² K⁴), find the energy radiated per second.

1. 887 J
2. 967 J
3. 1033 J
4. 1107 J

Correct answer: 887 J

Solution

P = sigma*A*T⁴ = 6.0e-8 * 1.6 * 310⁴ ≈ 887 W, i.e. ~887 J per second.

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