1. Suppose a woman does 500 J of work and -9400 J of heat transfer occurs into the environment in the process. (a) What is the decrease in her internal energy, assuming no change in temperature or consumption of food? (That is, there is no other energy transfer.) AE int J (b) The internal energy is stored energy due to food intake. Treating the change in internal energy as the input energy and work done as output, what is her efficiency? Efficiency, Eff: % (c) What physics law did you use in this problem? Zeroth Law of Thermodynamics First Law of Thermodynamics Second Law of Thermodynamics

1. Suppose a woman does 500 J of work and -9400 J of heat transfer occurs into the environment in the process. (a) What is the decrease in her internal energy, assuming no change in temperature or consumption of food? (That is, there is no other energy transfer.) AE int J (b) The internal energy is stored energy due to food intake. Treating the change in internal energy as the input energy and work done as output, what is her efficiency? Efficiency, Eff: % (c) What physics law did you use in this problem? Zeroth Law of Thermodynamics First Law of Thermodynamics Second Law of Thermodynamics

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter15: Thermodynamics

Section: Chapter Questions

Problem 27PE: This problem compares the energy output and heat transfer to the environment by two different types...

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