Thermodynamics: An Engineering Approach
8th Edition
ISBN: 9780073398174
Author: Yunus A. Cengel Dr., Michael A. Boles
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 4.5, Problem 23P
An ideal gas undergoes two processes in a piston–cylinder device as follows:
1–2 Polytropic compression from T1 and P1 with a polytropic exponent n and a compression ratio of r =V1/V2. 2–3 Constant pressure expansion at P3 = P2 until V3 = V1.
- (a) Sketch the processes on a single P-V diagram.
- (b) Obtain an expression for the ratio of the compression-to-expansion work as a function of n and r.
- (c) Find the value of this ratio for values of n = 1.4 and r = 6.
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A fixed mass of an ideal gas is contained in a piston-cylinder assembly. The pressure and temperature at the initial stage are P1 = 350 kPa and T1 = 600 K. The gas has a molecular weight M = 28 kg / kmol and the constant volume specific heat is Cv = 750 J / kg-K. The initial volume is V1 = 0.50 m^3. The gas is cooled slowly to T2 = 300 K while the pressure remains constant. Find the following:
The cylinder volume V2 after the gas has been cooled to 300 K.
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Chapter 4 Solutions
Thermodynamics: An Engineering Approach
Ch. 4.5 - An ideal gas at a given state expands to a fixed...Ch. 4.5 - Nitrogen at an initial state of 300 K, 150 kPa,...Ch. 4.5 - 4–3 The volume of 1 kg of helium in a...Ch. 4.5 - 4–4E Calculate the total work, in Btu, for process...Ch. 4.5 - 4–5 A piston–cylinder device initially contains...Ch. 4.5 - A pistoncylinder device with a set of stops...Ch. 4.5 - 4–7 A piston–cylinder device initially contains...Ch. 4.5 - 4–8 A mass of 5 kg of saturated water vapor at 300...Ch. 4.5 - 1 m3 of saturated liquid water at 200C is expanded...Ch. 4.5 - A gas is compressed from an initial volume of 0.42...
Ch. 4.5 - A mass of 1.5 kg of air at 120 kPa and 24C is...Ch. 4.5 - During some actual expansion and compression...Ch. 4.5 - 4–14 A frictionless piston–cylinder device...Ch. 4.5 - Prob. 15PCh. 4.5 - During an expansion process, the pressure of a gas...Ch. 4.5 - A pistoncylinder device initially contains 0.4 kg...Ch. 4.5 - 4–19E Hydrogen is contained in a piston–cylinder...Ch. 4.5 - A pistoncylinder device contains 0.15 kg of air...Ch. 4.5 - 1 kg of water that is initially at 90C with a...Ch. 4.5 - Prob. 22PCh. 4.5 - An ideal gas undergoes two processes in a...Ch. 4.5 - A pistoncylinder device contains 50 kg of water at...Ch. 4.5 - Prob. 26PCh. 4.5 - 4–27E A closed system undergoes a process in which...Ch. 4.5 - A rigid container equipped with a stirring device...Ch. 4.5 - A 0.5-m3rigid tank contains refrigerant-134a...Ch. 4.5 - A 20-ft3 rigid tank initially contains saturated...Ch. 4.5 - Prob. 31PCh. 4.5 - Prob. 32PCh. 4.5 - Prob. 33PCh. 4.5 - An insulated pistoncylinder device contains 5 L of...Ch. 4.5 -
4–35 A piston–cylinder device initially...Ch. 4.5 - Prob. 37PCh. 4.5 - A 40-L electrical radiator containing heating oil...Ch. 4.5 - Steam at 75 kPa and 8 percent quality is contained...Ch. 4.5 - Prob. 40PCh. 4.5 - An insulated tank is divided into two parts by a...Ch. 4.5 - Is the relation u = mcv,avgT restricted to...Ch. 4.5 - Is the relation h = mcp,avgT restricted to...Ch. 4.5 - Is the energy required to heat air from 295 to 305...Ch. 4.5 - A fixed mass of an ideal gas is heated from 50 to...Ch. 4.5 - A fixed mass of an ideal gas is heated from 50 to...Ch. 4.5 - A fixed mass of an ideal gas is heated from 50 to...Ch. 4.5 - Prob. 49PCh. 4.5 - What is the change in the enthalpy, in kJ/kg, of...Ch. 4.5 - Prob. 51PCh. 4.5 - Prob. 52PCh. 4.5 - Prob. 53PCh. 4.5 - Determine the internal energy change u of...Ch. 4.5 - Prob. 55PCh. 4.5 - Prob. 56PCh. 4.5 - Is it possible to compress an ideal gas...Ch. 4.5 - A 3-m3 rigid tank contains hydrogen at 250 kPa and...Ch. 4.5 - A 10-ft3 tank contains oxygen initially at 14.7...Ch. 4.5 - 4–60E A rigid tank contains 10 Ibm of air at 30...Ch. 4.5 - 4–61E Nitrogen gas to 20 psia and 100°F initially...Ch. 4.5 - An insulated rigid tank is divided into two equal...Ch. 4.5 - 4–63 A 4-m × 5-m × 6-m room is to be heated by a...Ch. 4.5 - 4-64 A student living in a 3-m × 4-m × 4-m...Ch. 4.5 - A 4-m 5-m 7-m room is heated by the radiator of...Ch. 4.5 - 4–66 Argon is compressed in a polytropic process...Ch. 4.5 - An insulated pistoncylinder device contains 100 L...Ch. 4.5 - 4–68 A spring-loaded piston-cylinder device...Ch. 4.5 - An ideal gas contained in a pistoncylinder device...Ch. 4.5 - Air is contained in a variable-load pistoncylinder...Ch. 4.5 - Prob. 71PCh. 4.5 - Prob. 72PCh. 4.5 - Prob. 74PCh. 4.5 - Prob. 75PCh. 4.5 - Prob. 76PCh. 4.5 - 4–77 Air is contained in a piston-cylinder device...Ch. 4.5 - A pistoncylinder device contains 4 kg of argon at...Ch. 4.5 - The state of liquid water is changed from 50 psia...Ch. 4.5 - During a picnic on a hot summer day, all the cold...Ch. 4.5 - Consider a 1000-W iron whose base plate is made of...Ch. 4.5 - Stainless steel ball bearings ( = 8085 kg/m3 and...Ch. 4.5 - In a production facility, 1.6-in-thick 2-ft 2-ft...Ch. 4.5 - Prob. 84PCh. 4.5 - An electronic device dissipating 25 W has a mass...Ch. 4.5 - Prob. 87PCh. 4.5 - 4–88 In a manufacturing facility, 5-cm-diameter...Ch. 4.5 - Prob. 89PCh. 4.5 - Is the metabolizable energy content of a food the...Ch. 4.5 - Is the number of prospective occupants an...Ch. 4.5 - Prob. 92PCh. 4.5 - Prob. 93PCh. 4.5 - Consider two identical 80-kg men who are eating...Ch. 4.5 - A 68-kg woman is planning to bicycle for an hour....Ch. 4.5 - A 90-kg man gives in to temptation and eats an...Ch. 4.5 - A 60-kg man used to have an apple every day after...Ch. 4.5 - Consider a man who has 20 kg of body fat when he...Ch. 4.5 - Consider two identical 50-kg women, Candy and...Ch. 4.5 - Prob. 100PCh. 4.5 - Prob. 101PCh. 4.5 - Prob. 102PCh. 4.5 - Prob. 103PCh. 4.5 - Prob. 104PCh. 4.5 - Prob. 105PCh. 4.5 - Prob. 106PCh. 4.5 - Prob. 107RPCh. 4.5 - Consider a pistoncylinder device that contains 0.5...Ch. 4.5 - Air in the amount of 2 lbm is contained in a...Ch. 4.5 - Air is expanded in a polytropic process with n =...Ch. 4.5 - Nitrogen at 100 kPa and 25C in a rigid vessel is...Ch. 4.5 - Prob. 112RPCh. 4.5 - Prob. 113RPCh. 4.5 - Prob. 114RPCh. 4.5 - 4–115 A mass of 12 kg of saturated...Ch. 4.5 - Prob. 116RPCh. 4.5 - Prob. 117RPCh. 4.5 - Prob. 118RPCh. 4.5 - Prob. 119RPCh. 4.5 - Prob. 120RPCh. 4.5 - Prob. 121RPCh. 4.5 - Prob. 122RPCh. 4.5 - Prob. 123RPCh. 4.5 - Prob. 124RPCh. 4.5 - Prob. 125RPCh. 4.5 - Prob. 126RPCh. 4.5 - Prob. 127RPCh. 4.5 - Prob. 128RPCh. 4.5 - A well-insulated 3-m 4m 6-m room initially at 7C...Ch. 4.5 - Prob. 131RPCh. 4.5 - Prob. 133RPCh. 4.5 - Prob. 134RPCh. 4.5 - An insulated pistoncylinder device initially...Ch. 4.5 - Prob. 137RPCh. 4.5 - Prob. 138RPCh. 4.5 - A pistoncylinder device initially contains 0.35 kg...Ch. 4.5 - Prob. 140RPCh. 4.5 - 4–141 One kilogram of carbon dioxide is compressed...Ch. 4.5 - Prob. 142RPCh. 4.5 - Prob. 143RPCh. 4.5 - Prob. 144FEPCh. 4.5 - A 3-m3 rigid tank contains nitrogen gas at 500 kPa...Ch. 4.5 - Prob. 146FEPCh. 4.5 - A well-sealed room contains 60 kg of air at 200...Ch. 4.5 - Prob. 148FEPCh. 4.5 - A room contains 75 kg of air at 100 kPa and 15C....Ch. 4.5 - A pistoncylinder device contains 5 kg of air at...Ch. 4.5 - Prob. 151FEPCh. 4.5 - Prob. 152FEPCh. 4.5 - A 2-kW electric resistance heater submerged in 5...Ch. 4.5 - 1.5 kg of liquid water initially at 12C is to be...Ch. 4.5 - An ordinary egg with a mass of 0.1 kg and a...Ch. 4.5 - 4–156 An apple with an average mass of 0.18 kg and...Ch. 4.5 - A 6-pack of canned drinks is to be cooled from 18C...Ch. 4.5 - An ideal gas has a gas constant R = 0.3 kJ/kgK and...Ch. 4.5 - Prob. 159FEPCh. 4.5 - Prob. 161FEP
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