MY NOTES ASK YOUR TEACHER PRACTICE (a) What is the best coefficient of performance for a heat pump that has a hot reservoir temperature of 53.3°C and a cold reservoir temperature of -12.2°C? (b) How much heat in kilocalories would it pump into the warm environment if 3.60 x 10 J of work (10.0 kW · h) is put into it? kcal (c) Assume the cost of this work input is 10c/kW h. Also assume that the cost of direct production of heat by burning natural gas is 81.0¢ per therm (a common unit of energy for natural gas), where a therm equals 1.055 x 10 ). Compare the cost of producing the same amount of heat by each method. cost of heat pump cost of natural gas Additional Materials

MY NOTES ASK YOUR TEACHER PRACTICE (a) What is the best coefficient of performance for a heat pump that has a hot reservoir temperature of 53.3°C and a cold reservoir temperature of -12.2°C? (b) How much heat in kilocalories would it pump into the warm environment if 3.60 x 10 J of work (10.0 kW · h) is put into it? kcal (c) Assume the cost of this work input is 10c/kW h. Also assume that the cost of direct production of heat by burning natural gas is 81.0¢ per therm (a common unit of energy for natural gas), where a therm equals 1.055 x 10 ). Compare the cost of producing the same amount of heat by each method. cost of heat pump cost of natural gas Additional Materials

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter3: The First Law Of Thermodynamics

Section: Chapter Questions

Problem 57P: An ideal gas expands isothermally along AB and does 700 J of work (see below). (a) How much heat...

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