Rotational Inertia Accessory - ME-8953

A disk and a ring permit several experiments in rotational inertia and conservation of angular momentum. Find the rotational inertia of the disk or ring using a Wireless Smart Gate or Photogate Head to measure the rotation of the Super Pulley. The disk can be mounted horizontally to measure its rotational inertia about the axis perpendicular to the center of the disk or vertically to measure the rotational inertia about its diameter.

When used in conjunction with the adapter, experiments using the parallel-axis theorem may be performed by moving the disk off from the center of rotation on the Rotating Platform. If the disk is mounted with the D-shaped hole down, the disk is locked in place on the Rotating Platform. As the platform rotates, the disk rotates and the student must use the Parallel Axis Theorem to derive the rotational inertia of the disk.

The ball bearing on one side of the disk permits it to rotate freely for some experiments, while a “D” hole on the other side prevents rotation about the disk axis. If the disk is mounted with the bearing side down, the disk has a bearing that allows it to rotate about its own axis. As the Rotating Platform rotates, the disk rotates relative to the platform, and thus the disk does not rotate relative to the table. The rotational inertia of the disk is the same as a point mass.