Balance a Stick on its End on a Finger/Mistake

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Source Work

1992: David Wells: Curious and Interesting Puzzles:

The Puzzles:
Henry van Etten


How can a stick be made to balance securely on the tip of a finger?

The solution is given as:

Force the tips of three knives into the stick, so that the knives hang well below the finger.
The centre of gravity of the entire arrangement will then be below the fingertip and will be stable.


You do not actually need as many as $3$ knives.

$2$ will do just as well.

In fact, any number of knives, as long as the points at which they are forced into the stick form a regular polygon, can be used.