3. Consider a reversible, isothermal expansion and a free expansion for a system. The system mass is 1.5 kg and is comprised of air with cp-1005 J/kg-k and R=287 J/kg-k. The volume of the system is increased by a factor of 3 for both processes. a) Determine the entropy change for the system during the isothermal expansion. Is heat transferred to or from the system during the isothermal expansion? b) Determine the entropy change for the system during the free expansion. c) For the isothermal expansion, what is the entropy change for the surroundings? State any assumptions you need to make. d) For the free expansion, what is the entropy change for the surroundings? e) Which process is reversible? Why? f) If the system's initial pressure is 100 kPa, what is the final pressure? Does the answer depend on which process we're talking about?

3. Consider a reversible, isothermal expansion and a free expansion for a system. The system mass is 1.5 kg and is comprised of air with cp-1005 J/kg-k and R=287 J/kg-k. The volume of the system is increased by a factor of 3 for both processes. a) Determine the entropy change for the system during the isothermal expansion. Is heat transferred to or from the system during the isothermal expansion? b) Determine the entropy change for the system during the free expansion. c) For the isothermal expansion, what is the entropy change for the surroundings? State any assumptions you need to make. d) For the free expansion, what is the entropy change for the surroundings? e) Which process is reversible? Why? f) If the system's initial pressure is 100 kPa, what is the final pressure? Does the answer depend on which process we're talking about?

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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