1K10.30 - Walk The Spool

Code Number:
Demo Title:
Walk The Spool
Forces and Friction
Area of Study:
Spools of different diameters with either rope or ribbon wound on the spindle.

Position the spool on the table so it has a few feet to roll.  If you pull on the ribbon when it is parallel to the table the spool will roll back toward you.  If you pull on the ribbon at an angle almost perpendicular to the table the spool will roll away from you.  You can then find the angle between these two cases where the spool can be made to slide on the table without rolling.

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Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist.  The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose.  The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources.  Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks.  These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage.  Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.