thermal engine uses up 200 J of heat energy per cycle, while its mechanical work output per cycle is 40 J. (a) What is this engine’s thermal efficiency? (b) If this engine is utilized to lift a 100 kg mass to a height of 20 m, through how many cycles does the engine have to be run to perform the lift (the answer may not be an integer)? (Hint: to lift a weight to a height, mechanical work must be performed against gravity.) (c) Consider now an ideal thermal engine operating between a hot reservoir and a cold reservoir. Find the temperature (in 0 C) that would be required for the hot reservoir in order to achieve the same efficiency as the engine in part (a) if the cold reservoir is at room temperature (25 0 C).

thermal engine uses up 200 J of heat energy per cycle, while its mechanical work output per cycle is 40 J. (a) What is this engine’s thermal efficiency? (b) If this engine is utilized to lift a 100 kg mass to a height of 20 m, through how many cycles does the engine have to be run to perform the lift (the answer may not be an integer)? (Hint: to lift a weight to a height, mechanical work must be performed against gravity.) (c) Consider now an ideal thermal engine operating between a hot reservoir and a cold reservoir. Find the temperature (in 0 C) that would be required for the hot reservoir in order to achieve the same efficiency as the engine in part (a) if the cold reservoir is at room temperature (25 0 C).

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.32P

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How can I work this problem out using this equation?