2. Problem No. 2: The horizontal platform ABCD weighs 60 lb and supports a 240-lb load at its center. The platform is normally held in position by hinges at A and B and by braces CE and DE. For this problem, assume that the brace DE is removed. a) Draw the free body diagram for the platform ABDC. How many unknowns are there in total? How many equations of equilibrium do you have? Is this problem statically determinate? Is the platform stable? b) Assume that the hinge at A does not exert any axial thrust (There is no reaction force in z direction at the hinge A). Determine the reactions at the hinges and the force exerted by the brace CE. N 2 ft B 3 ft. 4 ft E 300 lb X =======

2. Problem No. 2: The horizontal platform ABCD weighs 60 lb and supports a 240-lb load at its center. The platform is normally held in position by hinges at A and B and by braces CE and DE. For this problem, assume that the brace DE is removed. a) Draw the free body diagram for the platform ABDC. How many unknowns are there in total? How many equations of equilibrium do you have? Is this problem statically determinate? Is the platform stable? b) Assume that the hinge at A does not exert any axial thrust (There is no reaction force in z direction at the hinge A). Determine the reactions at the hinges and the force exerted by the brace CE. N 2 ft B 3 ft. 4 ft E 300 lb X =======

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter10: Virtual Work And Potential Energy

Section: Chapter Questions

Problem 10.46P: The uniform bar AB of weight W and length L is pinned to a sliding collar at A and to the sliding...

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