1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Help making an Electromagnet

  1. Apr 25, 2005 #1
    I am working on a physics project, and I need to build a strong electro magnet. I have previously made many real weak ones simply by coiling wire around a nail and conecting it to a AA battery(1.5V). Can anyone help me make a stronger version. I tried using a powersupply from an old computer, it plugged into a 120 V wall outlet and coverted AC to DC with outputs +5V, -5V, +12V and -12V. so I took the 12 and -12 leads and stripped them and connected them to a wire coiled around an iron pipe. however the powersupply then wouldn't kick on, as if a safety feature was preventing it, as soon as I disconnected one of the wires it would kick on, but then i didn't have an electromagnet. My idea was to use the 12 volt leads and transform them to high voltage low current to be safer, but for now I was just using the 12V as is. ONe idea my dad gave me was that possibly I need some resistance for the powersupply to work, so adding some resistors in series before the wire coil may work?

    So I need some instruction on making a much stronger electromagnet.
    Any help or weblinks would be appreciated
    Last edited: Apr 25, 2005
  2. jcsd
  3. Apr 26, 2005 #2
    could someone atleast give me some insight into what makes an electromagnet stronger, some of the things i know are the number of turns of wire in the magnet, as well as the curent or voltage applied to it.
    The reason i wanted to do it without just using batteries is because i didn't want to just have to connect 20 batteries together to get a high voltage. Maybe using the computer powersupply isn't possible however, again I cut the wires of one of the outputs that would connect to a hard drive, there are +12V, +5V, -5V, -12V. I connected one end of the wire coil to the +12 and one to the -12, am i going about this wrong, is there a different way i should be using this power supply, should I be connecting one end to the +12V and grounding the other?

    Any help would be great, this project is becomming evermore tedious
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook