From: donald.polvani at NGC.COM (Polvani, Donald G.)
Date: Wed Aug 10 10:35:38 2005
In my first college physics course, I saw this demonstration done in a
large lecture hall with the pendulum ball (about a foot in diameter)
suspended from the center of the ceiling. From the front of the room,
the professor released the pendulum ball from a spot directly in front
of his forehead. He didn't blink an eye as the ball swung away and then
returned almost to its original spot. There was absolute silence in the
room during the pendulum's swing. I was very impressed! Forty six
years later I am still impressed just thinking about it. He remarked at
the time, just as Ludwik suggests, that he had no concern because he
knew the laws of physics, and physics works!
Don Polvani
Northrop Grumman Corp.
-----Original Message-----
From: Forum for Physics Educators [mailto:PHYS-L@list1.ucc.nau.edu] On
Behalf Of Ludwik Kowalski
Sent: Wednesday, August 10, 2005 9:16 AM
To: PHYS-L@LISTS.NAU.EDU
Subject: Re: First Day Activities or Demos
OOPS, I just realized that pushing the large m away from your face is
likely to result in undesirable consequences. You should simply release
the mass at rest. To dramatize the show allow the initial angle to be
large, for example, by standing on a chair.
Sorry for the mistake.
Ludwik Kowalski
Let the perfect not be the enemy of the good.