Q- During a 2.5 hour run the metabolism of a marathon runner generates excessive body heat at an average rate of 4200 KJ per hour. Assume that the body (surface area 2.0 m2) loses heat at a rate of 50 W by convection.
a) Determine the rate at which radiation dissipates heat. Assume a skin temperature of 32 degrees C and an air temperature of 25 degrees C. The emissivity of the athlete’s skin is 0.80.
b) Determine the mass of swear that must evaporate per hour to keep the body temperature of the athlete constant during the race.
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