Problem 4 - Change in entropy system and surroundings The coils of the evaporator of a refrigeration system receives a saturated mixture of R-134a at 140 kPa and quality equal to 0.2. During the cooling process the refrigerant absorbs 180 kJ from the cooled space which is maintained at -5°C and leaves as saturated vapor at the same pressure. Please answer the following questions. Create a schematic of the system with the energy interactions across the boundary, include relevant temperature values. Based on what you know about the laws of nature, will the refrigerant be able to absorb heat? Why? Now assume that the total mass of refrigerant that received 180 kJ is equal to 1 kg. Determine the entropy change of the refrigerant, in kJ/K using four decimal places. Determine the entropy change of the cooled space, in kJ/K using four decimal places. Compute the total entropy change for this process, in kJ/K using four significant figures. List the assumptions that you used to solve this problem.

Problem 4 - Change in entropy system and surroundings The coils of the evaporator of a refrigeration system receives a saturated mixture of R-134a at 140 kPa and quality equal to 0.2. During the cooling process the refrigerant absorbs 180 kJ from the cooled space which is maintained at -5°C and leaves as saturated vapor at the same pressure. Please answer the following questions. Create a schematic of the system with the energy interactions across the boundary, include relevant temperature values. Based on what you know about the laws of nature, will the refrigerant be able to absorb heat? Why? Now assume that the total mass of refrigerant that received 180 kJ is equal to 1 kg. Determine the entropy change of the refrigerant, in kJ/K using four decimal places. Determine the entropy change of the cooled space, in kJ/K using four decimal places. Compute the total entropy change for this process, in kJ/K using four significant figures. List the assumptions that you used to solve this problem.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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