Rotational Motion Apparatus

thingiverse

Here is my take on a device designed by Steve Rea, which ended up being produced and sold by Arbor Scientific. The Rotational Inertia Demonstrator from Arbor works amazingly well and is very repeatable, making it highly recommended. The cost of this device is quite reasonable for its quality and construction. However, I decided to design a 3D printable version because our current physics teacher lacks the funds to purchase a class set. A string wrapped around one of the pulleys with a weight hanging from it is used in this setup. There are three different pulleys available to provide varying amounts of torque. With an extra set of hex nuts, washers can be positioned at different distances from the center of rotation, changing the moment of inertia. Several experiments can be conducted by students to investigate rotational motion. The diameters of the three pulleys are: - 24.5 mm - 49 mm - 73.5 mm **Update**: I have uploaded a new version with stops to prevent bearings from being pushed in too deep. This design was created using Tinkercad, and can be viewed at: https://tinkercad.com/things/53hXs6fGrxN