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1. (T/F) A two-force member has forces equal in magnitude and opposite in direction, acting along the same line of action. 2. (T/F) For moment equilibrium to be satisfied, three forces acting on a member must be concurrent or parallel. 3. (T/F) The Method of Joints is usually easiest to use when solving for all member forces in a truss. 4. The fundamental principle behind Method of Joints is a. Newton’s 3 rd Law of motion. b. Equilibrium: if the whole system is in equilibrium, then so is any part of the system. c. Moments: every force can be represented by a moment equal to force times distance, which simplifies truss analysis. d. Statical determinacy: we can determine the force carried by any member if we know the reactions caused by the loads. e. None of the above 5. (T/F) We denote truss members in compression and tension with vectors pointing into and away from their connection joints, respectively. 6-10. Fill in the blank on the right with the best choice. a. Truss l l More supports than necessary to hold the body in equilibrium b. Reactions l l Slender members joined together at their end points c. Method of Joints l l A consequence of restricted motion d. Redundant constraints l l Isolate a pin connection and apply equilibrium equations to f find connected member forces.
