My made solenoid doesnt induce magnetic field. What did I miss?

AI Thread Summary
The discussion revolves around a school project involving a solenoid that failed to induce a magnetic field. The user initially used a thin brown wire, which turned out to be insulated, preventing current flow. After switching to ordinary insulated copper wire, the LED lit up, indicating that the original wire was not conducting electricity. Participants suggested scraping off the insulation from the wire ends to ensure proper electrical connections. Ultimately, the user successfully resolved the issue by removing the insulation, allowing the solenoid to function correctly.
akamine
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Hey, I have a school project and I need a solenoid to induce a magnetic field.
http://www.yourpicbox.com/images/orhBIhKZq6426.jpg
I made a solenoid by winding a wire (I'm not sure what to call this wire. It's thin and brown.) to a pen case. I made 3 layers, 100-200 turns each.
When I tested it, connecting it to 6V DC, nothing happened. No magnet.

So I experimented other thing :
I connect a LED and 1.5V DC with this wire. LED didnt glow.
Then I change this wire with ordinary insulated copper wire. The LED glow brightly.

It seems that this wire doesn't conduct any current. What did I miss here?
 
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A solenoid like that can quickly drain power from the battery. Try another battery, or another power supply. Also, did you scrape the insulation on the wire when connecting to the battery?
 
Yes it sounds like you just haven't made proper connection to the ends of the wire. It often can be quite tricky to make a good electrical connection to enamelled wire. I recommend that you try the following procedure :

1. Burn off the insulation near the ends with a cigarette lighter.

2. Scrap away the burnt enamel with steel wool until you see shiny copper visible.

3. Solder short pieces of regular insulated copper wire (preferably "tinned" though it's not essential) to the ends where you're cleaned off the enamel. You'll find that this regular type wire is much easier to work with and make connection to your battery or other circuitry. Also, if you get the solder to stick well then you know the enamel is properly removed and the connections will be good.
 
As an alternative, it's also easy to scrape the insulation with sand paper.
 
thanks
I did not know the wire is insulated.
It works just fine after I scrap it :)
many thanks
 
akamine said:
thanks
I did not know the wire is insulated.

Think about it, if that wire wasn't insulated then all the turns would be touching each other and all you'd end up with is a big short circuit. :)
 
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