Estimate the change in the thermal energy of 100 g of copper (atomic weight - 63-5. Debye 0 - 348 K) when it is cooled (a) from 300 to 4 K. (b) from 78 to 4 K. and (c) from 20 to 4 K. If the latent hcat of liquid helium is 2700 JI-'. estimate how much helium would be required to produce the cooling in each case. (This calculation will over-estimate the quantity because the cooling power of the cold gas is neglected.)

Estimate the change in the thermal energy of 100 g of copper (atomic weight - 63-5. Debye 0 - 348 K) when it is cooled (a) from 300 to 4 K. (b) from 78 to 4 K. and (c) from 20 to 4 K. If the latent hcat of liquid helium is 2700 JI-'. estimate how much helium would be required to produce the cooling in each case. (This calculation will over-estimate the quantity because the cooling power of the cold gas is neglected.)

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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