1Q20.30 - Rolling Spool - Axles

Code Number:
Demo Title:
Rolling Spool - Axles
Rotational Energy - Axles
Area of Study:
Incline with non-slip surface, swivel clamp, fiberglass spool.

Set one end of the incline at a height of about 36 inches.  Place the axle of the spool on the incline and observe the velocity as it rolls down the incline.  When the spool touches the floor, it will take off at a much higher velocity than it had coming down the incline due to the greater diameter of the fiberglass disks as opposed to the diameter of the axle.



  • Jerome C. Licini, Richard O. White, George Awad, Yoon Jung Choi, "Enhanced Rolling Moment of Inertia Demonstration", TPT, Vol. 62, #2, Feb. 2024, p. 135.
  • Leonid Minkin, Anthony Zable, "Rotationsl-To-Translational Kinetic Energy Transfer for a Rolling Spool", TPT, Vol. 61, #9, Dec. 2023, p. 788.
  • William P. Boudreau, "Rolling Spool Experiment", TPT, Vol. 10, #8, Nov. 1972, p. 427.
  • J. Thomas Dickinson, "Rolling Spool Experiment", TPT, Vol. 10, #4, April 1972, p. 210.

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