Overall, 80% of the energy used by the body must be eliminated as excess thermal energy...

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Overall, 80% of the energy used by the body must be eliminated as excess thermal energy and needs to be dissipated. The mechanisms of elimination are radiation, evaporation of sweat (2,430 kJ/kg), evaporation from the lungs (38 kJ/h), conduction, and convection. A person working out in a gym has a metabolic rate of 2,500 kJ/h. His body temperature is 37°C, and the outside temperature 27°C. Assume the skin has an area of 2.0 m² and emissivity of 0.97. (= 5.6696 × 10-8 W/m². K4) (a) At what rate is his excess thermal energy dissipated by radiation? (Enter your answer to at least one decimal place.) W (b) If he eliminates 0.45 kg of perspiration during that hour, at what rate is thermal energy dissipated by evaporation of sweat? (Enter your answer to at least one decimal place.) W (c) At what rate is energy eliminated by evaporation from the lungs? (Enter your answer to at least one decimal place.) W (d) At what rate must the remaining excess energy be eliminated through conduction and convection? W Overall, 80% of the energy used by the body must be eliminated as excess thermal energy and needs to be dissipated. The mechanisms of elimination are radiation, evaporation of sweat (2,430 kJ/kg), evaporation from the lungs (38 kJ/h), conduction, and convection. A person working out in a gym has a metabolic rate of 2,500 kJ/h. His body temperature is 37°C, and the outside temperature 27°C. Assume the skin has an area of 2.0 m² and emissivity of 0.97. (= 5.6696 × 10-8 W/m². K4) (a) At what rate is his excess thermal energy dissipated by radiation? (Enter your answer to at least one decimal place.) W (b) If he eliminates 0.45 kg of perspiration during that hour, at what rate is thermal energy dissipated by evaporation of sweat? (Enter your answer to at least one decimal place.) W (c) At what rate is energy eliminated by evaporation from the lungs? (Enter your answer to at least one decimal place.) W (d) At what rate must the remaining excess energy be eliminated through conduction and convection? W

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olving for Energy Dissipation Rates a Radiation Calculate the StefanBoltzmann constant 567 108 WmK4 ... View the full answer