Question

PROBLEMS 13.42 A plank AB of mass m is placed in a truck so that its lower end rests against a crate on the bed while its upper part rests against the top of the railing as shown. If the truck moves to the right with an acceleration a, de- termine the maximum magnitude of a for which the plank will remain in contact with the top of the railing. 1.2 m 0.35 m Ci 043 42

Answer 1

a 1.2m tano (12 ) = 3-428 0.35m We for streme case, At point B, No reaction apply concept of Pseudo force on F.B.D B Pseudo force ma Taking the moment about A, R max e sino-mg x 2 mg wso =0 WsQ shaf sino ng ng А as g/tano tano. = 9.81 3.428 2.861m/? And Acceleration Hence, maximum magnitude of m/s² a = 2.861 m