(a) At a steam power plant, steam engines work in pairs,the heat output of the first one being the approximate heatinput of the second. The operating temperatures of thefirst are 750°C and 440°C, and of the second 415°C and270°C. If the heat of combustion of coal is 2.8 × 107 J/kg,at what rate must coal be burned if the plant is to put out950 MW of power? Assume the efficiency of the engines is65% of the ideal (Carnot) efficiency. (b) Water is used tocool the power plant. If the water temperature is allowed toincrease by no more than 4.5 C°, estimate how much watermust pass through the plant per hour.

Answered: (a) At a steam power plant, steam…

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

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Chapter4: The Second Law Of Thermodynamics

Section: Chapter Questions

Problem 92CP: Two moles of nitrogen gas, with =7/5 for ideal diatomic gases, occupies a volume of 102 m3 in an...

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