The Identical Bolts Riddle
There are two identical bolts that have been placed together so that their grooves fit into each other. If you move the bolts around each other while firmly holding the head so they do not rotate, will they: a. move inward, b. move outward, or c. remain the same distance from each other?
Think of a person walking up an escalator that is going down.
The heads of the bolts move neither inward or outward.