engineering Mechanics

1. Name:- Sunipa Bera
B.Tech CSE (CSF)
Roll no:- 02

3. Primarily I would thank God for being able to complete this project in Success.
Then I would like to thank my teacher, whose valuable guidance has been the
ones that helped me patch this project and make it full proof success his
suggestions and his instructions has served as the major contributor towards
the completion of the presentation.
Then I would like to thank my parents and friends who have helped me with
their valuable suggestions and guidance.
Acknowledgement

4. Basic Concepts
• Mechanics is the physical science concerned with the behavior of bodies that are
acted upon by forces.
• Statics is the study which deals with the condition of bodies in equilibrium
subjected to external forces.
• Dynamics is also a branch of mechanics in which the forces and their effects on
the bodies in motion are studied.
• Kinematics deals with the geometry of motion of bodies without and application
of external forces.
• Kinetics deals with the motion of bodies with the application of external forces.
• Hydromechanics is the study which deals with the conditions of fluid under
which it can remain at rest or in motion.
• Hydrostatics is the study of fluid at rest.
• Hydrodynamics is the study of fluid in motion.

5. Parallelogram law
The law of parallelogram of forces says
that if two vectors acting on a particle
at the same time be represented in
magnitude and direction by the two
adjacent sides of a parallelogram drawn
from a point their resultant vector is
represented in magnitude and direction
by the diagonal of the parallelogram
drawn from the same point .

6. Lami’s theorm
• According to this theorem, when three coplanar, concurrent and non-co-linear f
orces act on a body which is in equilibrium then the magnitude of each force is
proportional to the sine of angle between other two forces.
• This theorem can be proved by the sine law.
( A/Sin α) = ( B/Sin β) = (C/ Sin γ)

7. Resultants of force systems
• Resultant of a force system is a force or a couple that will have the same effect to the
body, both in translation and rotation, if all the forces are removed and replaced by the
resultant.
The equation involving the resultant of forces systems is as follows -
1. Rx= ΣFx = Fx1+Fx2+Fx3+…
The x-component of the resultant is equal to the summation of forces in the x-direction.
2. Ry= ΣFy = Fx1+Fx2+Fx3+...
The y-component of the resultant is equal to the summation of forces in the y-direction.
3. Rz= ΣFz = Fx1+Fx2+Fx3+...
The z-component of the resultant is equal to the summation of forces in the z-direction.

8. Forces and components
• Forces acting at some angle from the the coordinate axes can be resolved into
mutually perpendicular forces called components –
• x component
• y component
• If |F| is the magnitude and θ is the angle between the positive direction of the x-axis
and the force F, then the components Fx and Fy are given by
Fx = |F| cosθ and Fy = |F| sinθ
• Hence F may be written in terms of its components as follows
F = (Fx , Fy) = (|F| cosθ , |F| sinθ)