Date: Fri, 11 Oct 2002 11:06:23 -0700

Author: Doug Johnson

Subject: Re: breaking a glass with a speaker

Post:

I guess beaker size makes a difference. When I use the heavy duty 400ml
beakers(which is much smaller size than Berg uses), they break great! They
are just too expensive for us. So we use the standard Pyrex beakers. I
didn't mention it before, but I do set my beaker on a #8 rubber stopper. I
noticed that Ron Ebert uses a foam pad.
Oh, I did find something out a while ago, the tube on the end of the
speaker driver(if you have one) really needs to be adjusted to match the
approximate resonant frequency of the beaker. If it is too far off, then
all your volume/power won't get to the beaker. ...Doug J.

>We had an interesting experience regarding our beaker breaker that I have
>just finished solving.
>
>We have been getting beakers from the Chemistry department; whenever we
>need beakers we just go get a box or two. All of a sudden they stopped
>working. It turns out that Chenistry apparently got annoyed with all the
>breakage so they started getting heavier, stronger beakers and they were
>much more difficult to break. In fact, the character of the resonance
>changed entirely. So get cheap, thin beakers with a nice ring.
>
>Dick Berg
>
>***********************************************************************
>Dr. Richard E. Berg, Director Phone: (301) 405-5994
>Lecture-Demonstration Facility FAX: (301) 314-9525
>Department of Physics e-mail reberg@physics.umd.edu
>University of Maryland www.physics.umd.edu/lecdem
>College Park, MD 20742-4111
>***********************************************************************
>Illegitime non carborundum.
> -Joseph A. Ecclesine
>***********************************************************************


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