Message-Id: <v01540b05af73f966d35e@[192.174.2.170]>
Date: Fri, 11 Apr 1997 15:22:04 +0100
To: "Pinhole Listserv" <pinhole@exploratorium.edu>
From: emuller@exploratorium.edu (Eric Muller)
Subject: DC Motor
Hi Shelley,
On your DC motor, is there any insulation on either end of the coil?
If there is insulation-
If you have a copy of the snackbook, take a look at "Stripped Down
Motor" on page 97. The book describes a way of "turning off" the current to
the coil (electromagnet) by insulating one half of one end of the wire.
This allows the coil to spin through the region where the coil would be
attracted to the permanent magnet.
If there is no insulation on either wire end-
Look and see if the coil jiggles as it spins. Often, one side of
the coil will jump up and down and will, for a short period of time not be
in contact with the paper clip. This effectively stops the coil from being
an electromagnet for a split second, allowing it to spin through the region
where the coil would be attracted to the permanent magnet.
-Eric
Date: 10 Apr 1997 09:15:10 U
From: Seto1@aol.com
Subject: Re: Pinhole Daily Digest
Help!
I built a simple DC motor that consists of a D cell battery and 2 paper clips
to serve as electrodes and to support a coiled wire. A circular magnet was
placed on the battery. Since the current is DC and is never reversed, why
does the coil spin?
Thanks in advance,
Shelley Seto
Piedmont HS
Seto1@AOL.com
Eric Muller
Teacher-In-Residence
Exploratorium
3601 Lyon St.
San Francisco, CA 94123
415-561-0313
email:emuller@exploratorium.edu