NameChapter 24 ThermodynamicsCarnot EfficiencyA 25-kW heat engine operates between a 3200-K hot reservoir and a 450-Kcold reservoir. What is the engine's Carnot, or ideal, efficiency?Read and UnderstandWhat information are you given?Power of engine = 25 kWHigh-temperature reservoir, Thot = 3200 KClassLow-temperature reservoir, Tcold = 450 K=dePlan and SolveWhat unknown are you trying to calculate?Carnot efficiency = ?What formula contains the given quantity and the unknown?Thot-TeoldCarnot efficiency:ThotSubstitute the known values and solve.Note that because the hot and cold reservoir temperatures are given inkelvins, they can be directly substituted into the equation.Carnot efficiencyThot - TcoldThot3200 K-450 K3200 K=HOBS syna)2900= 0.86 or 86% ritottal onl obaIsmen 180Mghol sdt al dLook back and checkolarit niIs your answer reasonable? ob lliwYes, a high efficiency is expected due to the large difference between the Abreservoir temperatures.orii bsiMath Practicea separate sheet of paper, solve the following problems.te grien Inily n1. A heat engine has a hot-reservoir temperature of 1200°C. Its cold-reservoir temperature is room temperature air. What is the Carnotefficiency of the engine? (Note that room temperature air is about 25°C.)2. A heat engine has an efficiency of 52% when it runs with a hot-reservoirtemperature of 400°C and cold-reservoir temperature of 50°C. What isthe efficiency if the hot-reservoir temperature is raised to 800°C?

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On a separate sheet of paper, solve the following problems. vgrans grien Imusly 1. A heat engine has a hot-reservoir temperature of 1200°C. Its cold- reservoir temperature is room temperature air. What is the Carnot efficiency of the engine? (Note that room temperature air is about 25°C.) 2. A heat engine has an efficiency of 52% when it runs with a hot-reservoir temperature of 400°C and cold-reservoir temperature of 50°C. What is the efficiency if the hot-reservoir temperature is raised to 800°C?

On a separate sheet of paper, solve the following problems. vgrans grien Imusly 1. A heat engine has a hot-reservoir temperature of 1200°C. Its cold- reservoir temperature is room temperature air. What is the Carnot efficiency of the engine? (Note that room temperature air is about 25°C.) 2. A heat engine has an efficiency of 52% when it runs with a hot-reservoir temperature of 400°C and cold-reservoir temperature of 50°C. What is the efficiency if the hot-reservoir temperature is raised to 800°C?

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter15: Thermodynamics

Section: Chapter Questions

Problem 27PE: This problem compares the energy output and heat transfer to the environment by two different types...

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