Complete Analysis of Heat Engine Goal Solve for the efficiency of a heat engine using a five-step process the includes: 1. Making a state table. 2. Making a process table. 3. Calculating the totals for Work, Heat, and Internal-Energy-Change. 4. Identifying the heat input (hot reservoir) and output (cold reservoir). 5. Calculating the efficiency of the engine. Problem Shown in the figure to the right is a cyclic process undergone by a heat engine. Your heat engine shall use 6.0 moles of nitrogen gas (diatomic). During the process a->b, the pressure rises by a factor of 3.0. Solution P a T = 300 K P₁ = 100,000 Pa Engine Cycle isothermal (1) Fill in the State Table (all pressures in Pascals, all Pressure volumes in cubic meters, all temperatures in K). Volume Temperature 1.00e+3 0 300 33447.6 XXX 40200 1800 × 40200 0 Work Heat a- 0 74826 >b✓ (2) Fill in the Process Table (all entries in Joules). b- 49323 49323 <- 10 -74826 321017 du 74826 -74826 >a x Work = 49323 × J (3) Find the Totals: Heat = 49323 × J du = 10 ✔ J (4) Find the heat input (from "hot reservoir") and the heat output (to "cold reservoir"): Q-hot 124149 ✓ J Q-cold=74826 × (5) Find the efficiency of the engine: efficiency 39.7 × % V

Complete Analysis of Heat Engine Goal Solve for the efficiency of a heat engine using a five-step process the includes: 1. Making a state table. 2. Making a process table. 3. Calculating the totals for Work, Heat, and Internal-Energy-Change. 4. Identifying the heat input (hot reservoir) and output (cold reservoir). 5. Calculating the efficiency of the engine. Problem Shown in the figure to the right is a cyclic process undergone by a heat engine. Your heat engine shall use 6.0 moles of nitrogen gas (diatomic). During the process a->b, the pressure rises by a factor of 3.0. Solution P a T = 300 K P₁ = 100,000 Pa Engine Cycle isothermal (1) Fill in the State Table (all pressures in Pascals, all Pressure volumes in cubic meters, all temperatures in K). Volume Temperature 1.00e+3 0 300 33447.6 XXX 40200 1800 × 40200 0 Work Heat a- 0 74826 >b✓ (2) Fill in the Process Table (all entries in Joules). b- 49323 49323 <- 10 -74826 321017 du 74826 -74826 >a x Work = 49323 × J (3) Find the Totals: Heat = 49323 × J du = 10 ✔ J (4) Find the heat input (from "hot reservoir") and the heat output (to "cold reservoir"): Q-hot 124149 ✓ J Q-cold=74826 × (5) Find the efficiency of the engine: efficiency 39.7 × % V

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter3: The First Law Of Thermodynamics

Section: Chapter Questions

Problem 8CQ: A great deal of effort, time, and money has been spent in the quest for a so-called perpetual-motion...

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