Magnetic cooling can attain a temperature of roughly 0.05 K. In this technique, a high magnetic field is applied to a paramagnetic salt, which is kept at 5 K by transferring energy to a boiling liquid helium at low pressure. The salt is then thermally insulated from the helium, the magnetic field is removed, and the temperature of the salt decreases. Assume that a Carnot cycle heat pump removes 3 mJ from helium at an average temperature of 0.5 K. Determine the work input to the heat pump and the COP with an ambient temperature of 300 K.

Magnetic cooling can attain a temperature of roughly 0.05 K. In this technique, a high magnetic field is applied to a paramagnetic salt, which is kept at 5 K by transferring energy to a boiling liquid helium at low pressure. The salt is then thermally insulated from the helium, the magnetic field is removed, and the temperature of the salt decreases. Assume that a Carnot cycle heat pump removes 3 mJ from helium at an average temperature of 0.5 K. Determine the work input to the heat pump and the COP with an ambient temperature of 300 K.

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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