Question 6.P.1: Two uniform parallel beams AB 1.2 m long, weighing 20 kg eac...

Dynamics of Structures

Two uniform parallel beams $AB 1.2 m$ long, weighing $20 kg$ each, are hinged at $A$ and supported at $B$ by a spring of stiffness $4.33 N/mm$ as shown in Figure P6.1. The beams carry a flywheel of mass $132 kg$ attached at $D,1.0 m$ away from the hinge. The flywheel is rotating at $200 RPM$ and its center of gravity is offset $3 mm$ from the axis of rotation. Find (a) the natural frequency of the system, (b) the maximum vertical movement of end $B$ of the beams. Neglect damping.

p6.1

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