Introduction: Simple Homopolar Electric Motor

Here's a video I made a while back. It has had some pretty amazing popularity around the web and I thought I might as well include it here. It is not unique, but hopefully the video is helpful to some of you.


lolgirl (author)2009-01-07

i tried this thing but it dose not won't to work!!!!!!!!!!!!!!!

Bravehalospartan (author)lolgirl2012-11-05

Did u get a neo magnet, copper wire, and a fully charged battery

coniosis11 (author)2012-03-09

.....can you please give me a website that I can Buy a Magnets

Hobby lobby and Lowes

shoemaker (author)coniosis112012-03-09 - neodymium magnets round

CrashMGD (author)2009-11-10

There is no explination as to how this works. It is actually a small phenomenon

khaz (author)CrashMGD2012-03-09

It is a phenomenon, though not so small in my opinion. Any way the motor works just fine and fancy it is.
Phenomena of this kind have been described by physicists and electrical engineers for some decades. One wikipedia entry could be Force on a current-carrying wire . The formula which describes the force in case of a straight, stationary wire shows that the force is proportional, among other factors, to the current. In this case the current is significant, since it is a short-circuit current. This example of electrical engine is cute and fancy. Watching the video was great fun.
In the pictures below I tried to draw the model and the circuit.

popscott3 (author)2011-01-20

Can you use any kind of wire that is atracted to magnets?

shoemaker (author)popscott32011-01-21

No, use copper wire (not ferromagnetic) and a neodynium magnet with the silver metallic coating. The magnet has to be conductive and the wire has to NOT be attracted to a magnet.

is it okay if the neodyium magnet is small?

Yes, in fact the video has a link to another version of teh motor that uses a very small magnet. I guess there is some limit to how small the magnet can be.

walkingagh (author)2010-02-25

 So I am about 90% sure this is what is going on. What you have is a current that is flowing. Any flowing electric current produces a magnetic field and the the same way a moving magnetic field produces a current.

What is happening is that because the wire is coiled in a spiral, it is creating a magnetic field that is at an angle to field of the magnetic field of the magnet. This creates a force which spins the wire. Because turning the wire turns the magnetic field, it keeps on turning.

You could test this by 1) Reversing the turns to see if it reverses. or 2 Reversing the magnet which should also reverse it. If it's just "running away" then the magnet direction shouldn't matter.

walkingagh (author)walkingagh2010-02-25

 Just thought about it one more time, and reversing the coil won't work, but reversing the current, or the magnet will.

jkmerlin (author)walkingagh2011-05-24

Except the copper doesn't have to be spiraled to work...

spacecappa (author)2010-11-23

does it hav to be copper wire?

gadgetbadger (author)2008-04-09

Q: Why it works? A: Easy, You're a witch! ;)

daywalker42 (author)gadgetbadger2008-06-12

but how do you KNOW he's a witch?!

wouldnt he be a wizard

go watch monty python and the holy grail....then you'll get it

oh i feel stupid now, ive seen the movie i just was kinda "vegged" out when i red it... wow

burn her, burn her! Monty Python is such a great movie...

qwertyboy (author)trumpkin2008-09-02

it is a great movie, i love the part in the beginning with the cocunuts

Kaiven (author)qwertyboy2008-10-07

Where did you get coconuts? Are you suggesting coconuts migrate?

LiquidLightning (author)Kaiven2010-01-17

No! Maybe a bird carried them here!

 What? A Swallow carrying a coconut!

Well, Maybe 2 swallows!

Umbraa (author)trumpkin2010-02-09

Build a bridge out of her!!!!

geeklord (author)trumpkin2008-09-07

she's got a wart, and she's heavier than a duck!!! Burn her!!!

OBar (author)geeklord2009-08-06

Is she made of wood too?

seventhexile (author)daywalker422008-06-23

For starters Well, he turned me into a newt! ....I got better..

Umbraa (author)2010-02-09

 would it spin because of the way the electricity is flowing?

GorillazMiko (author)2008-04-08

Awesome! I want to try this out, so maybe I will. ;-)

OBar (author)GorillazMiko2009-08-06

The coconuts?

pocketsnzl (author)2009-07-19

its cos your attaching the wire to a negatively charged magnet and the positive terminal of the battery so your charging the wire negatively and its creating a circuit and the wire is trying not to touch the negatively charged shell if the battery so all it can do is spin around haaaaaaaa i like physics

taylor179 (author)pocketsnzl2009-08-04

lolololololololololololololololololololololololol rofl lmao i do believe you just powned him :) (no offence shoemaker)

timb12957 (author)2009-03-03

I can see that this could work. However things like the balance of the wire coil, how centered the battery is on the magnet, the amount of contact by the bottom of the wire, are all very critical. I made several attempts with different configurations. It would start to work, but stop before a full revolution. And be careful! Small gauge wire left in contact with the battery for just a little while becomes very HOT!

wolf555hound (author)2008-08-19

.... i just tried to connect the wire and the magnet with the tip, i got shocked. word to everyone, im an idiot, and dont connect the wire to magnet while adjusting the hook, lol

timb12957 (author)wolf555hound2009-03-03

No, you might have thought you got shocked. The sensation you received was you got burned. If you use a small gauge wire, it gets very hot when connected to the battery terminals. I got the same sensation and realized what it was.

eggman (author)wolf555hound2009-01-27

i want to know just how the hell you got shocked with 1.5V

Bridel568 (author)2008-12-03

I got this copper wire will that work? with or with out the insulation

acecraze (author)2008-04-22

hi! i just want to know if any type of magnet would work/ give the same results, otherwise, where can i get one like the one there? please answer!

shoemaker (author)acecraze2008-04-23

The magnet has to be electrically conductive. I suppose you could use a non-conductive magnet with a conductive washer or something sandwiched between it and the battery. You need a complete circuit from positive to negative poles of the battery. The batteries that I used are neodynium or rare earth magnets. I borrowed mine from work, but they are readily available on ebay or many other places over the net and at craft stores. These magnets are very strong and I'm sure that helps the motor work well/better, so other magnets might not work as well.

JamesRPatrick (author)shoemaker2008-12-02

I use a dead button battery with a large magnet underneath.

wolf555hound (author)shoemaker2008-08-19

also, if you find some or have some, magnetix have neodinium magnets, i think. i know there conductive.

joey2542667 (author)2008-11-28

will aluminum wire work? I tried it using that and it didn't work.

kk khrab (author)2008-07-08

nice i am going to make one right now but is it possible to make one with coin battery if yes can you send me an email thanks

shoemaker (author)kk khrab2008-07-10

sure, I would think that is possible, but everything would have to be smaller. I think that could be really cool.

livesteamfan (author)2008-07-01

Cool, and at the same time a little wierd.

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