Date: Tue, 25 Oct 2011 14:34:40

Author: --- Jerry DiMarco

Subject: Re: Image Current Demo


Following along with Steve's thought, if the effect is on magnetic
dipoles in a ferromagnetic material, why is this called an image current demo?


At 10/25/2011 03:56 PM, you wrote:
>Hummm, George, come to think of it, is this effect really any different
>from, say, the force that makes an iron core retract into a solenoid when
>the current is turned on? -- Steve
>You know how if you have an iron core for a solenoid, the core is pulled
>into the solenoid when current is run through
>On Oct 25, 2011, at 2:15 PM, George Herold wrote:
>>Just a though on another way to do this. If you have a nice coil for
>>making B-fields (I'm thinking of 1/2 of a Helmholtz pair.) And a
>>magnetometer... perhaps a simple hall probe. Then you can put a current
>>through the coil and make a B-field. Measure the size with the hall
>>probe. Now bring a large piece of iron near to the coil.. (from the side
>>opposite side of the hall probe) the field should increase. (Of course
>>ya gotta make sure the iron isn't magnetized already.)