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LectureNotes10
Use of Ideal Gas Equation
General Formulation
Assumption of quasi-equilibrium process allows us to use the ideal gas equation to represent
pressure within the system.
Isothermal Expansion
Isothermal expansion refers to expansion wor

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LectureNotes2
Estimating Avogardos Number. Benjamin Franklin is credited with experiments showing that
the size of molecules is very small and therefore the number of them in our engineering designs
is very large. His estimates are very crude. Fra

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LectureNotes3
CHARACTERISTICS OF THERMODYNAMIC SYSTEMS
Definitions
System: As previously discussed, the system is the part of the Universe that you wish to study.
Selecting the proper boundary of the system is often the first step necessary in sol

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LectureNotes4
Density
Mass (m): A measure of the quantity of matter. It is defined relatively to the mass corresponding
to a standard block (1 kg) of platinum-iridium alloy located in Sevres, France and is a scalar
quantity. A mass of 2 kg has twi

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LectureNotes5
Our relationships for the kinetic energies of molecules were derived for a constant volume
system. This measure of energy has been shown to be a good approximation of the internal
energy of monatomic gases (gases with only a single a

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LectureNotes6
Exact and Inexact Differentials
Overview of Concepts
One of the more confusing mathematical concepts in thermodynamics is the difference between
exact and inexact differentials. Most students are familiar with exact differentials.
We

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LectureNotes7
THE FIRST LAW
Mechanical Energy
Definitions
Mechanical energy is defined as the sum of kinetic and potential energies. Mechanical work is
easily illustrated using these energies. However, since the mechanical energy doesnt include
he

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LectureNotes8
Adiabatic process: Boundaries do not allow heating as mode of energy transfer, even if there is a
temperature difference between system and the surroundings. Adiabatic conditions are often
adequate if the system changes are rapid so

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LectureNotes9
Radiation
Radiation is a process where energy is transported by photons (or electro-magnetic waves) as a
consequence of changes in the configurations of atoms in the matter. Radiation is of fundamental
importance in understanding ene

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LectureNotes1
The word energy was first used by Thomas Young in 1807 for the kinetic and
potential energy associated with the mechanical motion of a mass attached to a
spring. It was not however, fully utilized until the second half of the century