Force lines is a method used in solid mechanics for visualization of internal forces in a deformed body. A force line is a curve representing graphically the internal force acting within a body across imaginary internal surfaces. The force lines show the maximal internal forces and their directions.
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Internal forces in the context of Statically indeterminate
Statically indeterminate is a condition when the equilibrium equations – force and moment equilibrium conditions – are insufficient for determining the internal forces and reactions on that structure. The term, and its opposite, statically determinate, are used in statics, structural mechanics, and mechanical engineering.
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