ENGR1100 Introduction to Engineering Analysis Lecture 16 Example

ENGR-1100 Introduction to Engineering Analysis Lecture 16

Example Bar AC rests against a smooth surface at end C and is supported at end A with a ball-and-socket joint. The cable at B is attached midway between the ends of the bar. Determine the reactions at supports A and C and the tension in the cable at B.

Z Az Ax Ay TBD FBE x C y

From a free-body diagram on the bar: The moment equilibrium: Z Az Ax x Ay TBD FBE C y

CONCEPT QUIZ (continued) 2. If an additional couple moment in the vertical direction is applied to rod AB at point C, then what will happen to the rod? A) The rod remains in equilibrium as the cables provide the necessary support reactions. B) The rod remains in equilibrium as the ball-and-socket joint will provide the necessary resistive reactions. C) The rod becomes unstable as the cables cannot support compressive forces. D) The rod becomes unstable since a moment about AB cannot be restricted.

ATTENTION QUIZ 2. What will be the easiest way to determine the force reaction BZ ? A) Scalar equation FZ = 0 B) Vector equation MA = 0 C) Scalar equation MZ = 0 D) Scalar equation MY = 0

Class assignment: Beam CD of the figure is supported at the left end C by a smooth pin and bracket and at the right end D by a continuous cable that passes around a frictionless pulley. The lines of action of the force in the cable pass through point D. Determine the components of the reaction at support C and the force in the cable when a 5 -k. N load W is being supported by the beam.