Inertia - Pen In Bottle

Purpose

To illustrate inertia of rest.

Equipment

Cola bottle, 12" embroidery hoop, and Pilot pen,

Suggestions

Balancing this thing requires a good deal of practice and/or skill!!

Images

c3-05

Description

The felt tip end of a Pilot pen is balanced on a 12" embroidery hoop, which in turn is balanced on a Coca-Cola bottle. Yanking the hoop out from under the pen by the leading side allows the pen to fall straight downward into the Cola bottle.

References

Martin Gardner, Physics Trick of the Month: Bottle, Hoop, and Dime TPT 32, 80 (1994).