1-1
SOLUTION MANUAL FOR
THERMODYNAMICS AN ENGINEERING
APPROACH 10TH EDITION BY CENGEL
CHAPTER (1-18) LATEST UPDATES
2025/2026 A+
1
, 1-2
TABLE OF CONTENTS
1) Introduction and Basic Concepts
2) Energy, Energy Transfer, and General Energy Analysis
3) Properties of Pure Substances
4) Energy Analysis of Closed Systems
5) Mass and Energy Analysis of Control Volumes
6) The Second Law of Thermodynamics
7) Entropy
8) Entropy Analysis
9) Exergy
10) Gas Power Cycles
11) Vapor and Combined Power Cycles
12) Refrigeration Cycles
13) Thermodynamic Property Relations
14) Gas Mixtures
15) Gas-Vapor Mixtures and Air-Conditioning
16) Chemical Reactions
17) Chemical and Phase Equilibrium
18) Compressible Flow
2
, 1-3
Thermodynamics
1-1 C On A Downhill Road The Potential Energy Of The Bicyclist Is Being Converted To Kinetic Energy, And Thus The Bicyclist
Picks Up Speed. There Is No Creation Of Energy, And Thus No Violation Of The Conservation Of Energy Principle.
1-2 C A Car Going Uphill Without The Engine Running Would Increase The Energy Of The Car, And Thus It Would Be A Violation Of
The First Law Of Thermodynamics. Therefore, This Cannot Happen. Using A Level Meter (A Device With An Air Bubble Between
Two Marks Of A Horizontal Water Tube) It Can Shown That The Road That Looks Uphill To The Eye Is Actually Downhill.
1-3 C There Is No Truth To His Claim. It Violates The Second Law Of Thermodynamics.
M ass, Force, And Units
1-4 C The “Pound” Mentioned Here Must Be “Lbf ” Since Thrust Is A Force, And The Lbf Is The Force Unit In The English System.
You Should Get Into The Habit Of Never Writing The Unit “Lb”, But Always Use Either “Lbm” Or “Lbf” As Appropriate Since The
Two Units Have Different Dimensions.
1-5 C In This Unit, The Word Light Refers To The Speed Of Light. The Light-Year Unit Is Then The Product Of A Velocity And Time.
Hence, This Product Forms A Distance Dimension And Unit.
1-6 C There Is No Acceleration, Thus The Net Force Is Zero In Both Cases.
1-7 E The Weight Of A Man On Earth Is Given. His Weight On The Moon Is To Be Determined.
Analysis Applying Newton's Second Law To The Weight Force Gives
W 32.174 Lbm Ft/S 2
W Mg M 210 Lbf Lbm
G 32.10 Ft/S 2
1 Lbf
Mass Is Invariant And The Man Will Have The Same Mass On The Moon. Then, His Weight On The Moon Will Be
W Mg (210.5 Lbm)(5.47 Ft/S 1 Lbf 3 5 .8 Lbf
2
)
32.174 Lbm Ft/S 2
1-8 The Interior Dimensions Of A Room Are Given. The Mass And Weight Of The Air In The Room Are To Be Determined.
Assumptions The Density Of Air Is Constant Throughout The Room.
Properties The Density Of Air Is Given To Be 1.16 Kg/M3.
ROOM
3 AIR
6X6X8 m3
, 1-4
Analysis The Mass Of The Air In The Room Is
M (1.16 Kg/M3 6 M3 ) 334 .1 Kg
Thus,
2 1N
W Mg (334.1 Kg)(9.81 M/S ) 1 Kg M/S 2 3277 N
4
SOLUTION MANUAL FOR
THERMODYNAMICS AN ENGINEERING
APPROACH 10TH EDITION BY CENGEL
CHAPTER (1-18) LATEST UPDATES
2025/2026 A+
1
, 1-2
TABLE OF CONTENTS
1) Introduction and Basic Concepts
2) Energy, Energy Transfer, and General Energy Analysis
3) Properties of Pure Substances
4) Energy Analysis of Closed Systems
5) Mass and Energy Analysis of Control Volumes
6) The Second Law of Thermodynamics
7) Entropy
8) Entropy Analysis
9) Exergy
10) Gas Power Cycles
11) Vapor and Combined Power Cycles
12) Refrigeration Cycles
13) Thermodynamic Property Relations
14) Gas Mixtures
15) Gas-Vapor Mixtures and Air-Conditioning
16) Chemical Reactions
17) Chemical and Phase Equilibrium
18) Compressible Flow
2
, 1-3
Thermodynamics
1-1 C On A Downhill Road The Potential Energy Of The Bicyclist Is Being Converted To Kinetic Energy, And Thus The Bicyclist
Picks Up Speed. There Is No Creation Of Energy, And Thus No Violation Of The Conservation Of Energy Principle.
1-2 C A Car Going Uphill Without The Engine Running Would Increase The Energy Of The Car, And Thus It Would Be A Violation Of
The First Law Of Thermodynamics. Therefore, This Cannot Happen. Using A Level Meter (A Device With An Air Bubble Between
Two Marks Of A Horizontal Water Tube) It Can Shown That The Road That Looks Uphill To The Eye Is Actually Downhill.
1-3 C There Is No Truth To His Claim. It Violates The Second Law Of Thermodynamics.
M ass, Force, And Units
1-4 C The “Pound” Mentioned Here Must Be “Lbf ” Since Thrust Is A Force, And The Lbf Is The Force Unit In The English System.
You Should Get Into The Habit Of Never Writing The Unit “Lb”, But Always Use Either “Lbm” Or “Lbf” As Appropriate Since The
Two Units Have Different Dimensions.
1-5 C In This Unit, The Word Light Refers To The Speed Of Light. The Light-Year Unit Is Then The Product Of A Velocity And Time.
Hence, This Product Forms A Distance Dimension And Unit.
1-6 C There Is No Acceleration, Thus The Net Force Is Zero In Both Cases.
1-7 E The Weight Of A Man On Earth Is Given. His Weight On The Moon Is To Be Determined.
Analysis Applying Newton's Second Law To The Weight Force Gives
W 32.174 Lbm Ft/S 2
W Mg M 210 Lbf Lbm
G 32.10 Ft/S 2
1 Lbf
Mass Is Invariant And The Man Will Have The Same Mass On The Moon. Then, His Weight On The Moon Will Be
W Mg (210.5 Lbm)(5.47 Ft/S 1 Lbf 3 5 .8 Lbf
2
)
32.174 Lbm Ft/S 2
1-8 The Interior Dimensions Of A Room Are Given. The Mass And Weight Of The Air In The Room Are To Be Determined.
Assumptions The Density Of Air Is Constant Throughout The Room.
Properties The Density Of Air Is Given To Be 1.16 Kg/M3.
ROOM
3 AIR
6X6X8 m3
, 1-4
Analysis The Mass Of The Air In The Room Is
M (1.16 Kg/M3 6 M3 ) 334 .1 Kg
Thus,
2 1N
W Mg (334.1 Kg)(9.81 M/S ) 1 Kg M/S 2 3277 N
4
