"Equilibrium is an extremely important concept because it provides us with an approach for determining unknown forces that act on a body. We understand that a body is in equilibrium if it is at rest or travelling at some constant velocity." p 4-1

CONCURRENT

CONCURRENT
TENDING TO CONVERGE TO ONE POINT

COPLANAR
FORCES OR LINES THAT ARE ORIENTED SO THAT THEY BOTH MAY LIE IN THE SAME SINGLE (IMAGINARY) PLANE (FLAT SURFACE OF INFINITE EXTENSION).

EQUATION
A MATHEMATICAL EQUALITY RELATING PARAMETERS OR MEASUREMENTS

EQUATIONS OF EQUILIBRIUM

EQUATIONS OF EQUILIBRIUM
THESE ARE FORMULAS INVOLVING BALANCED FORCES AND TORQUES THAT ALLOW ENGINEERS TO COMPUTE NECESSARY SUPPORTING FORCES SO THAT STRUCTURES CAN BE DESIGNED TO MATCH THEIR INTENDED APPLICATION.

EQUILIBRIUM
A STEADY-STATE CONDITION IN WHICH FORCES, TORQUES, FLOWS MAY BE HAPPENING BUT THE SYSTEM UNDER STUDY IS NOT CHANGING WITH TIME.

EQUILIBRIUM
A STATE OF BALANCE. FORCES, MOMENTS, FLOWS MAY BE OCCURRING IN A SYSTEM BUT NO NET CHANGE IS OCCURRING IN THE SYSTEM.

NON-CONCURRENT

NON-COPLANAR