Problem 5 - Heat and Thermodynamics A household refrigerator, rating COP=4.2 and power 195 W, absorbs heat from the freezer compartment at a temperature -13 °C and exhausts it into the room at 11 °C temperature. (a) 1.0 kg amount of water at room temperature is placed inside the freezer compartment. How much time it will take to freeze that water into ice at the freezer temperature? (b) Calculate the change in entropy of that amount of water as it undergoes from being at room temperature to become ice at freezer temperature. (Hint: In(1+x) = x when Ixl<1) (c) Calculate the change in entropy of the room's environment. Comment on the total change in entropy of the system with room and the refrigerator together.

Problem 5 - Heat and Thermodynamics A household refrigerator, rating COP=4.2 and power 195 W, absorbs heat from the freezer compartment at a temperature -13 °C and exhausts it into the room at 11 °C temperature. (a) 1.0 kg amount of water at room temperature is placed inside the freezer compartment. How much time it will take to freeze that water into ice at the freezer temperature? (b) Calculate the change in entropy of that amount of water as it undergoes from being at room temperature to become ice at freezer temperature. (Hint: In(1+x) = x when Ixl<1) (c) Calculate the change in entropy of the room's environment. Comment on the total change in entropy of the system with room and the refrigerator together.

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter15: Thermodynamics

Section: Chapter Questions

Problem 41PE: (a) What is the best coefficient of performance for a heat pump that has a hot reservoir temperature...

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