Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Ghost Detectors

  1. Jul 26, 2008 #1
    "Ghost Detectors"

    So I work at a popular tourist attraction that is well known for being "haunted." Needless to say, I get a lot of people asking about ghosts. I don't believe in ghosts. I need some kind of evidence to acknowledge stuff of the kind. Anyway, a week or two ago this couple showed up with a "ghost detector." I looked at it, and it was meter that measured milligauss. My physics class just blew over electromagnetism, so I only know what I've gathered from the internets. This is a measurement of the strength of an electromagnet field, yes? When I held it up to an exit sign, it went haywire. How significant is 1 milligauss? This thing went from like 1.5 to 6.0 milligauss.

  2. jcsd
  3. Jul 26, 2008 #2


    User Avatar
    Science Advisor
    Homework Helper

    Re: "Ghost Detectors"

    The earth's field is about 400-600 milli Gauss depending on where you live.
    Anything with AC wiring, a battery or an electric motor is going to give a significant field.

    Or maybe your exit sign is haunted!
  4. Jul 26, 2008 #3
    Re: "Ghost Detectors"

    So is there some reason the "normal" reading was like 1.5 milli gauss and not 400-600? Or is it a matter of me remember the scale wrong/a faulty unit (I doubt that ghost detectors maintain a high quality standard).

    Thanks for the info.

    EDIT: typo
    Last edited: Jul 26, 2008
  5. Jul 26, 2008 #4


    User Avatar
    Science Advisor
    Homework Helper

    Re: "Ghost Detectors"

    The scale might be measuring extra field, although if it was really measuring 1mGa you would get that by just moving it a fraction.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Ghost Detectors
  1. Smoke detectors (Replies: 4)

  2. Photon Detectors (Replies: 4)

  3. Detector error (Replies: 5)