Static Equilibrium of a Rigid Body
What is Static Equilibrium?
The condition when all acting forces cancel each other.
∑F=0
For a body to be in static equilibrium two things must be true:
1. It is rigid - no deflection, warping, elongation etc.
2. All acting forces cancel each other - it is not accelerating in any direction.
Steps to find static equilibrium:
1. Draw a FBD (Free-body diagram) of the body with all acting and reacting forces
as needed. Don’t forget a coordinate system!
2. Make equations to sum all forces and moments and set them equal to 0.
3. Solve for unknowns such that they make all the forces equal 0.
Equations to find the equilibrium of a rigid static body:
∑Fx=0
∑Fy =0
∑Fz =0
∑M =0
Static Equilibrium of a Rigid Body
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Static Equilibrium of a Rigid Body
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