Voltage gradient distortion in Copper when part is over a magnet

[Dc2LightTech]

TL;DR

will the Current in a thin sheet of copper be distorted as it passes over a strong magnet.

I am working with HS students on measuring Current Gradients in Copper for their science project " Current Gradients in the human body during surgical cauterization". Next year I was thing of putting a thin sheet of
Copper over strong magnets and using the Voltage gradient to draw the Current path. So, in a static setup with 5 Amps flowing through 1'x1' sheet of Copper with half of it placed of magnets will the Current path be distorted?

 

[DaveE]

TL;DR Summary: will the Current in a thin sheet of copper be distorted as it passes over a strong magnet.

in a static setup with 5 Amps flowing through 1'x1' sheet of Copper with half of it placed of magnets will the Current path be distorted?

Yes. But Cu is so conductive that it won't generate much voltage. That will be a very difficult measurement. Try to use a material that is resistive. Even then this is a difficult experiment, I think.

Check out "Hall Effect".

 

[Dc2LightTech]

in the picture I posted for voltage gradients, I have 4 amps at .2volts in the cu plate, would the gradient be distorted by neodymium magnets if only on the right side. I would buy them if it would be measurable difference.

 

[berkeman]

Yes. But Cu is so conductive that it won't generate much voltage.

Agreed.

So I was thinking about how to try to set up an experiment like this, and I agree that a more resistive material than Cu may work. I'm not sure what material to recommend (ESD foam is probably too resistive...), and it's labor intensive to solder together an x-y network of 1 Ohm resistors... If you could find a somewhat more resistive material than Cu, you might be able to use thermal imaging to see how the sheet of material was heating up from the current distribution. There are some pretty useful USB IR camera adapters that work with cellphones, for example:

https://www.flir.com/products/flir-one-gen-3/

One variation that I thought of might be fun, but I don't know if it would work. Perhaps if you set up a vertical water tank that was thin (maybe 0.5cm between the vertical Lexan plates) and make the fluid relatively conductive and set up a uniform bubble source at the bottom (with a voltage applied between the bottom and top of the tank to generate a vertical current parallel with the bubbles), you could play around with deflecting the up-traveling bubbles with a magnet that you hold up to the Lexan window. I'm not sure if it would work, so I need to think about it a bit more...

 

[DaveE]

Maybe buy a big silicon wafer on ebay?

 

[tech99]

What about resistance paper (Teledeltos) used for plotting currents.

 

[DaveE]

You'll also do better with an electromagnet and a big core to both generate a strong field and direct it to a large surface area.

 

[anorlunda]

How about using a fluid rather than a solid? The idea is to see the deflections visually rather than measure voltage differences. This video may be analogous.

 

[berkeman]

Maybe buy a big silicon wafer on ebay?

But won't it usually be passivated by $SiO_2$?