2C20.48 - Coanda Effect - Magnetic Ping - Pong Ball

Code Number:
Demo Title:
Coanda Effect - Magnetic Ping - Pong Ball
Bernoulli's Principle
Area of Study:
Heat & Fluids
Large Diameter Laminar Water Stream, and Ping-Pong Ball on a String.

Just as a ping-pong ball will be stable in an upward directed water stream, so will it be in a downward directed stream. Adjust the flow until you get a smooth steam. Put a string on a ping-pong ball and hold the string about 8 to 12 inches from the ball. Put the ball into the water stream and you can feel the stream "pulling" in the ball. You should be able to pull on the string at a large angle from the vertical before the ball can be pulled out of the stream.

  • T. López‐Arias, L. M. Gratton, S. Bon, and S. Oss, "'Back of the Spoon' Outlook of Coanda Effect", TPT, Vol. 47, #8, Nov. 2009, p. 508.
  • Robert Ehrlich, "H.10. Ping-Pong Ball Near a Water Stream, Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 105.
  • Martin Gardner, "14. A Table Tennis Ball Experiment", Smart Science Tricks, p. 27.
  • Joey Green, "Magnetic Ping-Pong Ball", The Mad Scientist Handbook, Vol. 2, p. 61.

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