Principles Of Engineering
© 2012 Project Lead The Way, Inc.
Statics
The study of forces and their effects on a system in a state of rest or uniform motion
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Statics Principles
Newton’s First Law of Motion (law of inertia):
An object in a state of rest or uniform motion will continue to be so unless acted upon by a net force
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Statics Principles
Newton’s Second Law of Motion:
The acceleration of an object is proportional to the net force acting on the object and inversely proportional to the object’s mass
Force = Mass x Acceleration
F = ma
Statics Principles
Newton’s Third Law of Motion:
For every action force, there is an equal and opposite reaction force
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Equilibrium
Static Equilibrium:
A condition where there is not a net external force acting upon a particle or rigid body and the body remains at rest or continues at a constant velocity
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Equilibrium
Translational Equilibrium:
The state in which there are no unbalanced forces acting on a body
F =0
F =0 x y
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Balanced
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Unbalanced
Equilibrium
Rotational Equilibrium:
The state in which the sum of all the clockwise moments equals the sum of all the counterclockwise moments about a pivot point
M=0
Remember
M=dxF
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Statics Principles
Scalar Quantities:
A physical quantity that has magnitude only
Examples: Mass, length,
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time, volume, temperature, pressure, and speed
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Statics Principles
Vector Quantities:
A physical quantity that has both a magnitude and
direction