Explanation Write the expression for the thermal efficiency. η = W cycle Q H (I) Here, the efficiency is η , the work done by the cycle is W cycle and the heat transfer from the high temperature source is Q H . Write the expression for the work done by the cycle. W cycle = Q H − Q C Here, the heat rejected is Q C Substitute Q H − Q C for W cycle in Equation (I). η = Q H − Q C Q H = 1 − Q C Q H (II) Write the expression for the efficiency in terms of temperature. η = 1 − T C T H (III) Here, the temperature of the cold reservoir is T C and the temperature of the hot reservoir is T H . Conclusion: Substitute 0.4 for η and 50 kJ for Q H in Equation (II)

Fundamentals of Engineering Thermodynamics

8th Edition

ISBN: 9781118832318

Author: MORAN

Publisher: WILEY

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It is generally related to thermal engineering which tells about the use, creation, conversion and transfer of heat energy between the systems. It is also considered that to transfer heat from one source to another, transfer of masses is also required. T…

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Chapter 5.11, Problem 21P

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The energy rejected.

The temperature of the cold reservoir.

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Chapter 5.11, Problem 20P

Chapter 5.11, Problem 22P

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The energy rejected. The temperature of the cold reservoir.