Pendulum Waves: Better than fireworks?


This Harvard physics apparatus uses a series of pendulums of varying lengths, swinging together, to make a mesmerizing dance:

The period of one complete cycle of the dance is 60 seconds. The length of the longest pendulum has been adjusted so that it executes 51 oscillations in this 60 second period. The length of each successive shorter pendulum is carefully adjusted so that it executes one additional oscillation in this period. Thus, the 15th pendulum (shortest) undergoes 65 oscillations.
Our apparatus was built from a design published by Richard Berg [Am J Phys 59(2), 186-187 (1991)] at the University of Maryland. The particular apparatus shown here was built by our own Nils Sorensen.

Strauss-Kahn case disintegrating

New York Times:

The sexual assault case against Dominique Strauss-Kahn is on the verge of collapse as investigators have uncovered major holes in the credibility of the housekeeper who charged that he attacked her in his Manhattan hotel suite in May, according to two well-placed law enforcement officials.

Although forensic tests found unambiguous evidence of a sexual encounter between Mr. Strauss-Kahn, a French politician, and the woman, prosecutors now do not believe much of what the accuser has told them about the circumstances or about herself.

Since her initial allegation on May 14, the accuser has repeatedly lied, one of the law enforcement officials said.

The accuser has not been seen by the public.  She is in protection.  She has been caught in one lie after another.  She has told authorities that 2 witnesses to her encounter were Moses and John Lennon.  While Strauss-Kahn might have a few problems with morals or scruples, there is something very disturbing about this case. 

Strauss-Kahn  has lost his  job and reputation.   Is it possible for someone to lose their lifetime achievements over a case like this that ends up with its chief witnesses being Lennon and Moses?  He was considered a serious contender for the French presidency.   Now he is being held on in the United States with a forfeited passport and is under strict house arrest. Read More