2B60.30 - Siphons, Self Starting Siphons, & Tantalus Cups

Code Number:
Demo Title:
Siphons, Self Starting Siphons, & Tantalus Cups
Pressure vs. Water Height
Area of Study:
Heat & Fluids
Skimit Magic Siphon, Homemade Glass Siphon, and Siphon with Squeeze Bulb.

Video Credit: Jonathan M. Sullivan-Wood.

Fill the Plexiglas cube nearly to the top with water. The homemade glass and the Skimit siphons are self starting. Insert and hang these on the edge of the Plexiglas cube. The siphon flow will start automatically.

The bulb siphon uses vacuum to draw the liquid up into the tube. The bulb may have to be squeezed several times to get the liquid to the proper height.

The Tantalus or Pythagorean cups are nothing more than self starting siphons. Very cool but watch out, you will get wet if you aren't careful!!

We have a variety of relaxation oscillators available.  Look at these webpages:

3A95.10 - Relaxation Oscillators

6-00.00 - Stroboscope (we have small variable frequency strobe lights available).

2B60.30 - Tantalus Cups

3D32.15 - Stadium Horn

4C30.25 - Geyser

4C31.30 - Drinking Bird

4C31.37 - Franklin's Pulse Glass Engine

5A40.70 - Kelvin Water Dropper

5F30.60 - Relaxation Oscillators - Neon Bulb, Doorbell, and Strobe Lights

10A06.10 - Relaxation Oscillators

13A10.10 - Perpetual Motion

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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.