Date: Wed Feb 14 17:18:08 2007
Author: Bernard Cleyet
Subject: Re: Incandescent Bulb Destruction and Uses
I thought WCM had the answer, and then he muffed it. The E resulting
from the collapse of the mag. field is prop. to the rate. The magnet
suppresses, just as a cap. does in auto. points, the arc.
bc, prays he isn't having a Sr. moment.
p.s. try using a DC P/S and a cap in parallel w/ the switch to verify.
[First try w/ ac.]
Jerry DiMarco wrote:
> I have a few questions before I hazard a guess. Does the magnet
> force you to change the method used to open the switch? Is the bright
> flash from the arc or the bulb? What was the intended result of this
> modification? Thank you...
> At 09:41 AM 2/14/2007, you wrote:
>> From: WC Maddox
>> If you have a large horseshoe magnet and a setup like
>> http://electro.physics.auburn.edu/~demo/em/5j/5j20_20.htm put the
>> switch contacts between poles of the magnet. When you jerk open the
>> switch you will get a bright flash. If you use 15 or 25 W bulbs the
>> filament is sometimes burned out. If anyone knows what is happening,
>> Dr. Williams at Auburn would like to know. He came up with this
>> modification of time delay experiment. It is more than the discharge
>> of the energy stored in coil and V=-Ldi/dt. The bulbs don't burn out
>> if you don't use magnet.
>> End Message
> Jerry DiMarco
> Manager of Lecture Demonstrations and Instructional Labs
> Montana State Univ., Physics Dept.
> Bozeman, MT
> Our Motto: "What would your mother do?"