Consider a structure consisting of three bars joined in a vertical line hanging from a top support.
(a) Write down the equilibrium equations for this system when only forces and displacements in the vertical direction are allowed, i.e., a onedimensional structure. Is the problem statically determinate, statically indeterminate or unstable? If the latter, describe all possible mechanisms and the constraints on the forces required to maintain equilibrium.
(b) Answer part (a) when the structure is two- dimensional, i.e., is allowed to move in a plane.
(c) Answer the same question for the fully three- dimensional version.