PHYSÝCS

posted by .

Suppose a person metabolizes 2150 kcal/day.

a) With a core body temperature of 37.1°C and an ambient temperature of 21.3°C, what is the maximum (Carnot) efficiency with which the person can perform work?

b) If the person could work with that efficiency, at what rate, in watts, would they have to shed waste heat to the surroundings?

c) With a skin area of 1.51 m2, a skin temperature of 26.7°C, and an effective emissivity of e = 0.610, at what net rate does this person radiate heat to the 21.3°C surroundings?

d) The rest of the waste heat must be removed by evaporating water, either as perspiration or from the lungs. At body temperature, the latent heat of vaporization of water is 575 cal/g. At what rate, in grams per hour, does this person lose water?

e) Estimate the rate at which the person gains entropy. Assume that all the required evaporation of water takes place in the lungs, at the core body temperature of 37.1°C.

  • PHYSÝCS -

    hhf

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    A person falls in water at 0 degrees C. After 20 minutes of exposure, they are suffering acute hypothermia, as their core body temperature has dropped to 30.0 degrees C. Assume that a person’s heat capacity can be approximated by …
  2. physics

    A person's body is producing energy internally due to metabolic processes. If the body loses more energy than metabolic processes are generating, its temperature will drop. If the drop is severe, it can be life-threatening. Suppose …
  3. Physics

    A person consumes 2500 kcal/day while expanding 3500 kcal/day. In a months' time, about how much weight would this person lose if the loss were essentially all from body fat?
  4. math

    Newton’s Law of Cooling states that the temperature of a heated object decreases exponentially over time toward the temperature of the surrounding medium. The temperature u of a heated object at a given time t can be modeled by the …
  5. math

    Newton’s Law of Cooling states that the temperature of a heated object decreases exponentially over time toward the temperature of the surrounding medium. The temperature u of a heated object at a given time t can be modeled by the …
  6. math-urgent please help

    Newton’s Law of Cooling states that the temperature of a heated object decreases exponentially over time toward the temperature of the surrounding medium. The temperature u of a heated object at a given time t can be modeled by the …
  7. math-urgent

    Newton’s Law of Cooling states that the temperature of a heated object decreases exponentially over time toward the temperature of the surrounding medium. The temperature u of a heated object at a given time t can be modeled by the …
  8. Physics

    A person's body is producing energy internally due to metabolic processes. If the body loses more energy than metabolic processes are generating, its temperature will drop. If the drop is severe, it can be life-threatening. Suppose …
  9. physics

    Suppose a person metabolizes 2250 kcal/day. a) With a core body temperature of 36.9°C and an ambient temperature of 21.5°C, what is the maximum (Carnot) efficiency with which the person can perform work?
  10. thermodynamics

    There are 46 person in a room that has diameter of 14 ft x 30 ft x 34 ft. the initial pressure and temperature are 14.7 psi and 60.8 F. Each person givs off 150 kcal/hr. assume that room is completely sealed off and 0.2 cu.meter per …

More Similar Questions