1F20.36 - Embroidery Hoop and Pen

Code Number:
Demo Title:
Embroidery Hoop and Pen
Inertia of Mass
Area of Study:
Milk bottle, embroidery hoop, marker or pen.

Balance the embroidery hoop over the mouth of the milk bottle.  Place the pen on the top of the hoop directly over the mouth of the bottle (Positions are marked on the hoop).  With a sweeping motion snatch the hoop out from under the pen.  The pen will fall into the milk bottle.

  • Martin Gardner, "Bottle, Hoop, and Dime", TPT, Vol. 32, #2, Feb. 1994, p. 80.
  • Martin Gardner, "Bottle, Hoop, and Dime", Science Tricks, p. 39.

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