Date: Wed, 29 Aug 2001 14:20:31 -0400

Author: Nils Sorensen

Subject: Re: Pendulum Waves demonstration


Hello Tappers,

The pendulum video Dick Berg put up was so neat that I
decided to film the pendulum waves demo I just finished yesterday. It
has 15 bobs (drawer pulls) that are suspended with a bifilar system.
This is indeed the way to hang them. The string is a yellow
florescent braided fishing string and looks great in a UV light. This
particular model will pass through four durations (total time=4min)
before the amplitude is diminished too much to see. Have a look if
interested. It is listed under Physics Videos.

I thought the faculty would use this to describe phase relationships.
Could this also be a demonstration of harmonics?


>Dick and Dan,
> Thanks so much for putting the Pendulum Waves Demo up to be viewed at
>your website. Awesome! I am sure it took a lot of work to do that. The
>quicktime version was good enough for me, but the Mpeg was just wonderful!
>I couldn't view the other two on my G4 computer so I can't rate them.
>Maybe I will try the other two from my computer tonight.
>Thanks again. ....Doug
>>In response to the recent discussion of the pendulum waves demonstration,
>>Dan and I (mainly Dan) have made a video of one complete cycle of the
>>motion of the pendula. To see it, go to
>>then select the format that you want. You have a compromise between
>>download time and quality, as indicated on the list.
>>The video was taken in digital NTSC composite format using a Canon XL1
>>camera, and the videos were constructed from that data using Adobe
>>Premiere. This is an example of what Dan described in his talk at the
>>summer meeting.
>>Let Dan know what you think is the best compromise by e-mail at
>>Dick Berg
>>Experience is something you don't get until just after you need it.
>>Dr. Richard E. Berg, Director Phone: (301) 405-5994
>>Lecture-Demonstration Facility FAX: (301) 314-9525
>>Department of Physics e-mail
>>University of Maryland
>>College Park, MD 20742-4111