1. A closed vertical cylinder containing 0.3 kg of nitrogen at 90 °C is fitted with a weighted, frictionless piston so that a constant pressure of 275 kPa is maintained on the gas. The nitrogen is stirred by a paddle wheel inserted through the cylinder wall until the absolute temperature of the gas is doubled. During the process, 20 kJ of heat is transferred from the nitrogen to the surroundings. Determine the amount of paddle-wheel work required for this process. [Ans: -101.1 kJ]

1. A closed vertical cylinder containing 0.3 kg of nitrogen at 90 °C is fitted with a weighted, frictionless piston so that a constant pressure of 275 kPa is maintained on the gas. The nitrogen is stirred by a paddle wheel inserted through the cylinder wall until the absolute temperature of the gas is doubled. During the process, 20 kJ of heat is transferred from the nitrogen to the surroundings. Determine the amount of paddle-wheel work required for this process. [Ans: -101.1 kJ]

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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ASAP
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