a) A heat engine operates at a 40% efficiency. The heat input is 20,000 J. How much work does this engine produce? b) Assume that the efficiency listed is the Carnot efficiency. What is the ratio of temperature of the cold reservoir to temperature of the hot reservoir? c) If the real ratio of temperature of the cold reservoir to temperature of the hot reservoir was less than you found in (b), would this engine violate the 2nd Law of Thermodynamics? Explain.

a) A heat engine operates at a 40% efficiency. The heat input is 20,000 J. How much work does this engine produce? b) Assume that the efficiency listed is the Carnot efficiency. What is the ratio of temperature of the cold reservoir to temperature of the hot reservoir? c) If the real ratio of temperature of the cold reservoir to temperature of the hot reservoir was less than you found in (b), would this engine violate the 2nd Law of Thermodynamics? Explain.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.46P

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