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Question
Assume that the total surface area of a human body is 1.6 m2 and that it radiates like an ideal radiator. Calculate the amount of energy radiated per second by the body if the body temperature is 37°C. Stefan constant σ is 6.0 × 10−8 W m−2 K−4.
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Solution
Given:
Area of the body, A = 1.6 m2
Temperature of the body, T = 310 K
From Stefan-Boltzmann law,
`"Energy radiated"/"Time" = sigma"AT"^4`
Here, A is the area of the body and `sigma` is the Stefan-Boltzmann constant.
Energy radiated per second = 1.6 × 6 × 10−8 × (310)4
= 886.58 ≈ 887 J
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