A heat engine operates with sink temperature 25° with the efficiency of 30%. By howmany kelvins should be raised for the source temperature to achieve an efficiency of 40%.(а) 78 K(b) 69 K(c) 52 K(d) 71 K

Given, here Temperature of Heat sink is TC and initial and final efficiencies are denoted as η1 and…

Answered: A heat engine operates with sink…

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter18: Heat Engines, Entropy, And The Second Law Of Thermodynamics

Section: Chapter Questions

Problem 2OQ

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A heat engine operates with sink temperature 25° with the efficiency of 30%. By how many kelvins should be raised for the source temperature to achieve an efficiency of 40%. (а) 78 K (b) 69 K (c) 52 K (d) 71 K