1Q30.90 - Magic Windmill | Instructional Resources and Lecture Demonstrations

Code Number:

1Q30.90

Demo Title:

Magic Windmill

Condition:

Excellent

Principle:

Transverse Oscillations to Elliptical Oscillations

Area of Study:

Acoustics

Disclaimer

Equipment:

Propeller on a stick

Procedure:

The magic windmills will show elliptical oscillation in a solid. When the notches are rubbed with another stick the rotor will rotate in a preferred direction depending where the index finger touches the notched stick. Hold the index finger on the left side of the notched stick will make the rotor turn in the counter-clockwise direction. Hold on the right side and the rotor will turn in the clockwise direction.

References:

Gordon J. Aubrecht, II, "A Mechanical Toy: The Gee-Haw Whammy-Diddle", TPT, Vol. 20, # 9, Dec. 1982, p. 614 - 615.
D. P. Jax Mulder, "Children's Toys", TPT, Vol. 18, # 2, Feb. 1980, p. 134.
Susan S. Welch, "What Makes It Turn?", TPT, Vol. 11, # 5, May 1973, p. 303.
Jearl Walker, "1.161, Rotor on a Notched Stick", The Flying Circus of Physics Ed. 2, p. 74.
Tik Liem, "The Yip-Yip Stick", Investigation to Science Inquiry, p. 354.
David Kutliroff, "43, An Apparent Failure of the Law of Conservation of Momentum", 101 Classroom Demonstrations and Experiments For Physics Teachers, p. 98.
Martin Gardner, "38, The Mysterious Whimmy Diddle", Smart Science Tricks, p. 60.
Janice VanCleave, "86, Wizard Stick", Teaching the Fun of Physics, p. 127.
"Watch the Hand - A Skidoo-Skidee Trick", The Boy Magician, ISBN 978-1-58816-754-5, p. 138.
2.68, Jearl Walker, "Magic Windmill", The Flying Circus of Physics with Answers.

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