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Definition of “Mechanics”
Science concerned with the motion of bodies under
the action of forces, including the special case in
which a body remains at rest. Of first concern in the
problem of motion are the forces that bodies exert
on one another. This leads to the study of such topics
as gravitation, electricity, and magnetism, according
to the nature of the forces involved. Given the forces,
one can seek the manner in which bodies move
under the action of forces; this is the subject matter
of mechanics proper.
-------Encyclopædia Britannica
Classification of “Mechanics”
~studies of motion and the cause of motion~
Statics
Load/Deformation/Stress/Strain/Strain Energy
Kenematics
Dynamics
{
Kenetics
{
Displacement
{
Force/Torque
Velocity
Acceleration
Energy/Momentum
Concept of Stress
Rubber
is stronger than
Steel
100 kg
Rubber
100 kg
Steel ???
From Force to Stress
Prismatic Bar under Axial Load
More Rigorous Definition of Stress
Shear Force and Shear Stress
Examples of Shear Force Transmission
Single Lap Shear and Double Lap Shear
Average Bearing Stress in Pin Joint
Stress on Oblique Plane
Stress under General Loading
Components of Stress
2-D Plane Stresses
Allowable Stress and Safety Factor
su
sa?
sallowable = sultimate /(Safety Factor)