This apparatus is designed to demonstrate the oscillation of pendulum with bifilar and trifilar suspension. Solid cylinder, hollow cylinder and a bar is suspended with two or three threads. In bifilar suspension, translational and rotational oscillations will produce and in case of trifilar torsional vibrations will produce.
Mass moment of inertia can be calculated by the period of oscillation of torsion oscillation. In this apparatus bracket is attached with the base plate. Cylinder or bar is attached with the bracket with two or three supports, length of the suspension thread can be varied by the threaded supports.