1C20.20 - Free-Fall - Time Intervals

Code Number:
Demo Title:
Free-Fall - Time Intervals
Acceleration Due to Gravity
Area of Study:
Washers or Weights Tied to Fishing Line at Prescribed Intervals.

Washers or lead weights are tied to a fishing line at intervals of 1, 4, 9, 16, 25, etc.  Pull the line over a high pulley until all the washers are off the ground.  When released the sound of the washers hitting the ground will occur at equal intervals.

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  • Borislaw Bilash II, “Falling Down“, A Demo A Day – A Year of Physical Science Demonstrations, p. 214.

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.