Message-Id: <l0311070bb34693701ba1@[192.174.2.173]>
In-Reply-To: <371FAE3D.C6020C09@ousd.k12.ca.us>
Date: Fri, 23 Apr 1999 13:19:26 -0800
To: "Pinhole Listserv" <pinhole@exploratorium.edu>
From: Paul Doherty <pauld@exploratorium.edu>
Subject: Re: pinhole Leyden jar
Hi Tim
The Leyden jars are very sensitive to following directions carefully, and
there are enough steps that it can be hard for some groups to get them to
work.
For example it is important to hold the aluminum foil outside of the can in
a persons hand while the central nail electrode is touched to the metal pie
pan of the electrophorus.
This allows the external charge to move to ground, or from ground.
The classroom humidity usually rises during the day. Humid air discharges
the styrofoam more quickly. In dry air if you rub the styrofoam vigorously
for 15 seconds it will hold its charge for minutes, in humid air it will
discharge in under a minute. So some speed in using the electrophorus is
called for.
I'm glad it worked, mostly.
Paul D
Paul "But it is more complicated than that!" Doherty,
Senior Staff Scientist, The Exploratorium.
pauld@exploratorium.edu, www.exo.net/~pauld