Applied Physics

1. TOPICS:
THERMODYNAMICS:
1ST LAW OF THERMODYNAMICS AND ITS EXAMPLES:
2ND LAW OF THERMODYNAMICS AND ITS EXAMPLES:
SUBJECT:
APPLIED PHYSICS
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2. ASSIGNED BY:
DR. SHAMSHAD ALI
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PRESENTED BY:

3. AFTABSIKANDER (F16TE65)
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BY
THERMODYNAMICS
AND
EXAMPLES

4. What is Thermodynamics ?
Therme (heat), dynamic (motion)
Heat is form of energy
“Thermodynamics is the branch of science that deals with energy transfer and
its effect on the system.”
“study of thermal engineering.”
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5. •SURROUNDING:
•SYSTEM:
•BOUNDARY:
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Fig 1.4

6.  SYSTEM:
“The quantity of matter under consideration.”
The system may be quantity of steam, piston or a cylinder but following must be
specified:
Quantity and Composition of matter:
Temperature, Pressure and Energy:
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7. • “The combination of matter and space external to the system that may be
influenced by change in system.”
BOUNDARY:
• “The thermodynamic system and surrounding are separated by envelope
called boundary.”
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SURROUNDING:

8. SYSTEMS:
There are three systems in thermodynamics classified on the basis of
exchange of energy and mass:
OPEN SYSTEM:
CLOSED SYSTEM:
ISOLATED SYSTEM:
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9. • Exchanges heat.
• Exchanges mass:
• Examples:
car engine
cup of tea
boiling water etc.
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OPEN SYSTEM:

10. • Exchanges energy:
• No exchange of mass:
• For example:
• Motor car battery:
• Battery cell etc.
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CLOSED SYSTEM:

11. 11
ISOLATED SYSTEM:
• Neither energy changes:
• Nor mass changes:
• Also called fixed system:
• Examples:
• Water cooler:
• Thermo flask:

12. Examples:
Steam boiler:Locomotive engine in train:
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Tidal Power:

13. 1ST LAW OF
THERMODYNAMICS
BY. M FAIZAN ALI (F16TE30)
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EXAMPLES:
BY NEERAJ SONI (F16TE68)

14. 1st LAW DEFINE AS:
• The 1st law of thermodynamics is usually referred to as the Law of
Conversion of Energy, i.e. Energy can neither be created nor be
destroyed, but it can transfer from one form to another form.
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Internal energy:
• It is define as, the energy associated
with the random disorder motion of
molecules.

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Low grade energy:
MAIN EQUATION OF 1ST LAW

16. APPLICATIONS OF FIRST LAW OF
THERMODYNAMICS:
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• There are four main applications of thermodynamics known as processes:
• ISOTHERMAL PROCESS:
• ISOCHORIC PROCESS:
• ISOBARIC PROCESS:
• ADIABATIC PROCESS:

17. ISOTHERMAL PROCESS:
• Iso (same, constant), thermal (heat, energy).
• A system in which temperature of the system
remains constant.
• According to main equation:
Q = ΔU + W
So we have:
Q = W
.:ΔU = 0
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.
Before After

18. ISOCHORIC PROCESS:
• Iso (same, constant), choric (volume).
• Such a process in which volume does not
change by changing pressure or temperature or
both.
• According main equation:
Q = ΔU + W
So we have
Q = ΔU
.: W = f.d = 0 18
Before After

19. ISOBARIC PROCESS:
• Iso (same, constant), bar (pressure).
• In this process, pressure remains unchanged.
• According to main equation:
Q = ΔU + W
So we have
Q = ΔU + W
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Before After

20. ADIABATIC PROCESS:
A (not), dia (across), batos (passable).
A process in which nothing is given externally.
According to main equation:
Q = ΔU + W
So we have
W = - ΔU
.: Q = 0 20
Before After

21. DIESEL ENGINE:
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ELECTRIC KETTLE:
o The Conversion of mechanical energy into heat.
o Conversion of electrical energy into heat energy.

22. 2nd LAW OF
THERMODYNAMICS
BY AYAZ ALI (F16TE76)
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EXAMPLES:
SADAM HUSSAIN (F16TE05)

23. The second law of thermodynamics may be defined as:
“Heat can not flow itself from colder body towards the hotter body
without any external work.”
This law is also used to determine the theoretical limits for the performance
of mostly used engineering systems like heat engines and heat pump.

24. •Heat always flows from hot body to cold body.

25. If we want to transfer the heat from cold body to hot body so we have to perform
external work.
Cold
body
Hot
body

26. KELVIN-PLANK STATEMENT:
• It is impossible to construct a device as heat engine
that operates in a cycle and produces:
• No effect other than transfer of heat:
• Gives 100% efficiency.
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27. CLAUSIUS STATEMENT:
• This statement is considered as the transformation of heat in two hot
reservoir
•
• It is impossible for a self acting machine working in a cyclic process to
transfer energy from lower temperature body towards higher temperature
body without any external force.
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28. Similarities in Both Statements:
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Kelvin-Plank Statement: Clausius Statement
Applied on:
heat engine.
Applied on:
heat pump:
refrigerator.
Only based on:
observations.
Only based on:
observations.
Mathematically:
No mathematical proof.
Mathematically:
No mathematical proof.

29. • We all know that doing work on the water will generate
heat.
• However transferring heat to the liquid will not generate
work.
• Yet, doing so does not violate the first law as long as the
heat added to the water is the same as the work gained
by the shaft.

31. • A heating device that moves from low to
High temperature.
• Heat pump absorb heat from low
temperature source and supplies the
heat to a warmer medium.
• Heat pump is a special device beacause
heat can not convert low teperature to
high temperature.

32. • Refrigerator is a cyclic device , and the
working fluids used in the cycle is called
refrigerator .
• Refrigerator is to maintain the
refrigeraterd space at a low temperature.

33. • Dr. D.S Kumar, applied thermodynamics, basic concept and laws of
thermodynamics, year 2012, page no 01.
• S C Gupta, thermodynamics, system boundary and surrounding, year
2008, page no 06.
• M.Achuthan, engineering thermodynamics, classification of systems, 2nd
edition, year 2011, page no 18-19.
• Onsager, L. (1931). "Reciprocal Relations in Irreversible
Processes". Phys.Rev.37.
• Belkin, A.; et, al. (2015). "Self-Assembled Wiggling Nano-Structures and
the Principle of Maximum Entropy Production". Sci. Rep. 5
• Ziegler, H. (1983). An Introduction to Thermo mechanics. North Holland,
Amsterdam.
• Engineering thermodynamics page no:132
• Born, M. (1949), p. 31
• Pippard, A.B. (1957/1966), p. 16.
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ANY QUESTION…?

35. OF
BUNDLE THANKS