2. A. Matter consists of widely spaced atoms in the gas phase. However, it is
very convenient to ignore the atomic nature of matter and see it as a
continuous homogeneous substance without holes, that is, a continuum.
Continuity idealization makes it possible to treat properties as point
functions and to assume that properties vary continuously in space
without jumps.
3. In a continuous approach, fluid properties such as density, viscosity,
thermal conductivity, temperature, etc. can be expressed as continuous
functions of space and time.
1.
2.
3.
CONCEPT
3. MACROSCOPIC APPROACH MICROSCOPIC APPROACH
In this approach, a certain quantity of matter is
considered without taking into account the
energy occurring at Molecular level. This is
known as classical Thermodynamics
In this approach, the energy occurring at the
molecular level is taken into account for analysis.
The values of these energies are constantly
changing with time. This is known as statistical
Thermodynamics
The analysis of macroscopic systems
requires simple mathematical formulae
The behaviour of the system is found by using
statistical method as the number of molecules is
very large.
COMPARISION OF MICROSCOPIC
AND MACROSCOPIC APPROACH
4. The values of the properties of system are their
average values.
Example: consider a sample of a gas in a closed
container. The pressure of the gas is the average
value of the pressure exerted by millions of
individual molecules
The properties like velocity momentum impulse
kinetic energy force of impact etc e which describe
the molecule e cannot be easily measured by y
instruments. Our senses cannot feel them.
In order to describe such a system only a
few variables are needed
Large number of variables are needed to
describe such a system So the approach is
complicated.
5. POINT AND
PATH FUNCTION
They are introduced to identify the variables of thermodynamics.
Path function: Their magnitudes depend on the path followed during a process as well as the end states. Work (W), heat (Q) are path
functions.
Process A: W=10 kJ
Process b: WB-7kJ
Point function: They depend on the state only, and not on how a system reaches that state. All properties are point functions.
Process A: V₂-V,3 m³
Process B: V-V₁=3 m³
6. Irreversible process: entropy increase
Entropy is a property of a thermodynamic system that expresses
the direction or outcome of spontaneous changes in the system
Reversible process: entropy change zero
ENTROPY
9.
Meet The
Group
Priyansh Kashyap Priyanshu Bhardwaj Yash Kumar Lucky Bisht Aman Kumar Singh
Question
Answer
Entropy Point And
Path Function
Introduction Differences
