A runner generates 1260 w thermal energy. If this heat has to be removed only by

Question

A runner generates 1260 w thermal energy. If this heat has to be removed only by evaporation, how much water does this runner lose in 15 minutes of running? The latent heat vaporization of water is 22.6 times 105 J/kg. A jogger is running outdoors on a cold day when the temperature is -20.0degree C. She is breathing at the rate of 25 breaths per minute, and each time she breathes in she inhales 0.00450 m^3 of air. How much heat does she lose from breathing during 20.0 minutes of jogging if the air in her lungs is heated to her body temperature of 37.0degree C before it is exhaled? The specific heat of air is and the density of air under typical conditions is 1.29 kg/m^3.

Explanation / Answer

1260 W = 1260 J/sec

1260J/sec * 15 minutes * 60 seconds / minute = 1134000

amount of water that evaporates total energy by the heat of vaporization of water

1134000/ 22.6 x 105 = 0.501 kg

= 50 G me ans

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.