"I decided to take advantage of the conservation of angular momentum. The ruler is trying to rotate one way and fall, the head of the hammer is trying to fall as well. However, because of this the back of the hammer is producing an opposite turning force counteracting the falling force of the ruler, thus producing this very strange and unbelievable result.
The string is only used to hold the ruler and hammer together. There is nothing holding the ruler in place. As you can see the hammer is not touching the underside of the table.
I have made a video (on YouTube) which I recorded whilst the apparatus was set up and shows it from some more angles"
Content Jan Skakle j.skakle at abdn.ac.uk
Last updated July 2009