1 Role of Thermodynamics and it’s applica-
tions in Engineering and Science
Thermodynamics is the science of the relationship between heat, work and
the properties of substances. Heat and work are intimately connected through
energy, and hence Thermodynamics is defined as the study of energy. Energy
is essential and vital component of our life, hence knowledge of Thermody-
namics is essential for all of us. In addition, engineers and those aspiring
to be engineers, need to master the fundamental as well as applications of
Thermodynamics, in order to be able to effectively practice the engineering
profession.
2 Macroscopic and Microscopic viewpoints
In microscopic,our attention is focused on single molecule and the changes
that occur at molecular level is considered. But in macroscopic it is not
the same. The molecules within a specific volume considered are assumed
to have same behaviour and the analysis is carried out assuming the same
behaviour through out the volume.
2.1 Microscopic view point :
• in microscopic approach,our attention is focused on each and every
molecule to know the behaviour of the system.
• it is also called “ stastical thermodynamics”
• it is useful for low density materials
• the properties like velocity, momentum, kinetic energy can be mea-
sured.
• large number of variables are required to describe the system. so ap-
proach is complicated.
• molecular theory of matter is assumed.
2.2 Macroscopic view point:
• in macroscopic approach, our attention is focused on certain quantity
of matter without going the event occuring at molecular level.
1
tions in Engineering and Science
Thermodynamics is the science of the relationship between heat, work and
the properties of substances. Heat and work are intimately connected through
energy, and hence Thermodynamics is defined as the study of energy. Energy
is essential and vital component of our life, hence knowledge of Thermody-
namics is essential for all of us. In addition, engineers and those aspiring
to be engineers, need to master the fundamental as well as applications of
Thermodynamics, in order to be able to effectively practice the engineering
profession.
2 Macroscopic and Microscopic viewpoints
In microscopic,our attention is focused on single molecule and the changes
that occur at molecular level is considered. But in macroscopic it is not
the same. The molecules within a specific volume considered are assumed
to have same behaviour and the analysis is carried out assuming the same
behaviour through out the volume.
2.1 Microscopic view point :
• in microscopic approach,our attention is focused on each and every
molecule to know the behaviour of the system.
• it is also called “ stastical thermodynamics”
• it is useful for low density materials
• the properties like velocity, momentum, kinetic energy can be mea-
sured.
• large number of variables are required to describe the system. so ap-
proach is complicated.
• molecular theory of matter is assumed.
2.2 Macroscopic view point:
• in macroscopic approach, our attention is focused on certain quantity
of matter without going the event occuring at molecular level.
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