: Is it possible to make an electromagnet w 2 like ends?

AI Thread Summary
Creating an electromagnet with two like poles at both ends is theoretically challenging due to the fundamental nature of magnetic poles, which require opposite poles to exist. The discussion highlights that reversing the wire direction at the midpoint may lead to significant repulsive forces between the two ends. Additionally, the magnetic field generated would likely cancel out in the center, resulting in weak poles at the ends. Suggestions include using a Hallbach Array to manage the magnetic field distribution and exploring the use of separate Hallbach poles to achieve the desired effect. Understanding the properties of materials and their hysteresis curves is also emphasized for effective design.
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HELP!

Is it possible to create an electromagnet with one continuous wire with 2 like poles (i.e. both ends either north or south)?.

Visualising it with the right hand screw rule for current carrying coils, it will be like the picture below, but one end of the coil will be as shown, while the other end of the electromagnet will be coiled in the other direction as dictated by the right hand screw rule pointing to the right, to give both extreme ends North, with 2 South pole ends in the middle.

Right-Hand-Grip-Rules2.png


Right now in my head it seems possible to create this kind of electromagnet, given that i can find a way to keep the coils from messing up when a current passes through it.

Is this actually possible? What are some complications that you may foresee or ways to make it work if it can't?

Thank you so much.
 
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Looks to me like you could reverse the direction of the wire as it wraps around at the midpoint. But then you have a very large repulsive force between the two parts of the coil.
 
that's what I'm thinking too, but it seems plausible so far
 
Think about the flux in the centre of the coil. As you bring the two halves together they will tend to cancel each other.
 
You can't have a north pole (or poles) without a south pole somewhere. This is true no matter what kind of magenet you are talking about: permanent, electro-, or hybrid. Once the position of the poles is specified, then one can think about where the wires go.
 
Vanadium 50 said:
You can't have a north pole (or poles) without a south pole somewhere. This is true no matter what kind of magenet you are talking about: permanent, electro-, or hybrid. Once the position of the poles is specified, then one can think about where the wires go.

I was under the assumption that the south poles would be in the middle and the field would look similar to placing two bar magnets together with their south poles touching.
 
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You will discover that a "pole" mid-magnet gives you very weak poles at the ends.
 
How about with the middle section being a Hallbach Array to keep those "like-poles" in the center from fighting -( can weld and-or anneal as needed in order to maintain or achieve single-mass-lump to minimize magnetic noise & echo due to physical alteration passing through material interfaces), and changing wire-wrap direction in transition over or through Hallbach material. As a side-note, that echo an be used in measurement just as surely as ultrasound showing a pipewall-water interface, if one can catch it on the bounce, a bit like water flowing against main current ;) -- if you wish to study water currents more look up Viktor Schauberger's water work.

also look into Municipal Solid Waste Separation - using magnets to pull out ferrous materials - and induced eddy-currents to PUSH out aluminum cans etc, a beautiful design and execution

also look into the hysteresis curves of your materials, find your smoothest transition metals for Hallbach

if it need not be a single solid unit then maybe try sticking two Hallbach-ed poles end-to-end with whatever pole you want facing out? Think about those 50lb pull cheap magnets from Harbor Freight with their Hallbach latch-plates.

good luck and happy tinkering
 
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Thank you all for the responses.

Vanadium 50 said:
You will discover that a "pole" mid-magnet gives you very weak poles at the ends.

Can you please elaborate more on why that will happen? My grasp of magnetism isn't that strong. :/
 
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