Question

1. A flywheel is suspended by resting the inside of the rim on a horizontal knife edge so that the wheel can swing in a vertical plane. The flywheel has a mass of 350Kg. The knife edge is parallel to and making 350mm from the axis of the wheel. The time for making one small oscillation is 1.77 seconds. Assuming that the centre of mass is in the axis of the wheel, determine:
(I).The radius of gyration of the wheel about the axis.
(II). The torque to increase the speed of the flywheel at uniform rate from 240 rev/min to 250 rev/min in 0.75seconds when the flywheel is revolving about its axis.
2. A solid metal cylinder 450mm diameter is suspended with its axis vertical by means of a wire coaxial with the cylinder and rigidly attached to it. The stiffness of the wire is 22Nm per radian of twist. Find the necessary mass of the cylinder so that when it is given a small angular displacement about its axis, it will make 40 vibrations per minute.​

Answer 1

Answer: A fly wheel having a mass of 30kg was allowed to swing as pendulum about a knife edge at inner side of the rim as shown in figure.

Explanation: