Chapter 1 : Introduction 1
2. Sub-divisions of Theory of
3. Fundamental Units.
4. Derived Units.
5. Systems of Units.
6. C.G.S. Units.
7. F.P.S. Units.
8. M.K.S. Units.
9. International System of
Units (S.I. Units).
13. Presentation of Units and
14. Rules for S.I. Units.
16. Resultant Force.
17. Scalars and Vectors.
18. Representation of Vector
19. Addition of Vectors.
20. Subtraction of Vectors.
The subject Theory of Machines may be defined as
that branch of Engineering-science, which deals with the study
of relative motion between the various parts of a machine,
and forces which act on them. The knowledge of this subject
is very essential for an engineer in designing the various parts
of a machine.
Note:A machine is a device which receives energy in some
available form and utilises it to do some particular type of work.
Sub-divisions of Theory of Machines
The Theory of Machines may be sub-divided into
the following four branches :
1. Kinematics. It is that branch of Theory of
Machines which deals with the relative motion between the
various parts of the machines.
2. Dynamics. It is that branch of Theory of Machines
which deals with the forces and their effects, while acting
upon the machine parts in motion.
3. Kinetics. It is that branch of Theory of Machines
which deals with the inertia forces which arise from the com-
bined effect of the mass and motion of the machine parts.
4. Statics. It is that branch of Theory of Machines
which deals with the forces and their effects while the ma-
chine parts are at rest. The mass of the parts is assumed to be
2 Theory of Machines
The measurement of
physical quantities is one of the
most important operations in
engineering. Every quantity is
measured in terms of some
arbitrary, but internationally
fundamental units. All
physical quantities, met within