Re: Cloud chamber experiment

["H.B. Knowles" <hbknowles@hbknowles.com>]

At 17:36 04/14/2000 Friday, you wrote:
> This is a multi-part message in MIME
> format.
> --------------B06EC0D1E9AB59CDC9935194
> Content-Type: text/plain; charset=us-ascii
> Content-Transfer-Encoding: 7bit
>
> I just received a call from a local HS science teacher. He wants to do a
> cloud
> chamber experiment with his students. He wants to try first before he
> does it
> before his class. And he requested me to help him. I have not done
> this
> experiment myself. I look through my old nuclear physics books and got
> some
> ideas. Our plan is: 1) get a glass jar, 2) place a black peace of paper
> in the
> bottom of the jar, 3) saturate the jar with alcohol vapor, 4) place the
> jar in
> dry ice, 5) place a radiation source or observe cosmic radiation in the
> cloud
> chamber. I have Coleman mantle for source.
>
> My questions are: 1) will this work? 2) do we need to be in dark
> place?
>
> I really want ot help this teacher. Any constructive suggestions are
> welcome. The
> teacher would like to do this on next Friday if possible so we have to
> use what
> we have.

Mr. Jo: I haven't looked at the details on how to set up such a
"cloud chamber" for years, but it sounds right. 

What we have here is a problem in experimental physics: you may have to
adjust some aspects here & there to make it . Work. But no one can
tell you with certainty that it will work, the way you have set it
up. I would for example. recommend well washed Petri dishes  to keep
the system clean and free from dust and grease. I think the operation
would work best in moderate light. But the point is, don't ask us, go try
it and find out for yourself. There is-in this case, anyhow- no penalty
for doing it wrong and a great deal of satisfaction in fiddling with it
until you do it right. It is a real addiction, laboratory work, and one
worth acquiring. 

Go try it!

H.B. Knowles, PhD, Physics Consulting

4030 Hillcrest Rd, El Sobrante, CA 94803

Phone (510)758-5449

Fax (510) 758-5508

hbknowls@ix.netcom.com (until 1/31/00)

hbknowles@hbknowles.com (new)

<www.hbknowles.com>