Statics -- from Eric Weisstein's World of Physics

Statics is the study of the conditions under which mechanical and other systems remain in a configuration ("state") which does not change with time. Statics theory is based on five axioms:

1. A rigid body acted upon by two forces is in a state of static equilibrium if and only if the two forces are of the same intensity, lie along the same line of action, and are oriented in opposite directions along the line.

2. If a system of two forces in equilibrium is added to or extracted from a given system of forces, the way that the system of forces acts on a rigid body undergoes no change.

3. The resultant of two forces acting at the same material point is equal to the vector sum of the two forces. The line of the resulting force's action contains the material point. This axiom obeys the principle of vector summation.

4. Two interacting bodies react on each other with two forces of equal intensity, and along the same line of action, but in opposite directions along the line. This axiom is also known as principle of action and reaction.

5. If a deformable body is in a state of static equilibrium, it would also be in static equilibrium if the body were rigid. This axiom is also known as the principle of solidification.

Dynamics, Kinematics, Mechanics, Static Equilibrium

References