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Effect of spinning magnets on gauss readings

  1. Dec 25, 2012 #1
    My question is about the strength of magnets and how the strength is affected when you spin a magnet. When I use my meter to read the gauss of a permanent magnet I don't get much of a reading at all. However, when I spin the magnet the reading becomes very strong bouncing the needle quite high or showing a high reading on a digital meter as well.

    Is this truly an accurate reading or is the spinning magnet actually influencing the meter to give incorrect high readings? The main reason I ask is I'm trying to learn all I can about emf and how it affects your health and I would like to know if things such as my fish tank motor, which can give readings off the chart of my meters, are truly a potential health issue or just showing a faulty gauss.

    I tried to web search but kept running into MRI websites. If someone has a link that explains this it would be very much appreciated.

  2. jcsd
  3. Dec 25, 2012 #2


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    Staff Emeritus
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    What kind of meter are you using?

    And no, your fish tank motor is not a hazard to your health. There is nothing you can buy at a best buy, wal mart, or other similar store that will be a hazard to your health if you use it correctly. Only ionizing radiation, that of the UV range and above, or EXTREMELY high strength static fields can do any harm to you. (And only extremely high strength electric fields at that) Unfortunately the internet is so full of crappy nonsense claiming that electromagnetic fields are harmful to you that it is very difficult to find out the truth. Multiple health studies conducted over decades has shown no link between normal everyday EM fields or low frequency/intensity radiation and health problems. I wish I had a reference to give you. Perhaps a search of PF using the search function will turn up a relevant thread on the subject with a proper reference.
  4. Dec 26, 2012 #3
    I have a trifield 100xe and a lutron emf-822a. Maybe we can steer clear of the health side as I know of some studies currently going on that may very well show lower levels do in fact impact health, especially children.

    I guess I just want to know if a gauss reading on something like a running motor is actually accurate with these types of meters. It just seems like a single static magnet reading versus the same magnet spinning is very different and I'm unsure if it is an actual reading or an influence on the meter.

    I'll keep searching the web too.
  5. Dec 26, 2012 #4


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    Gold Member

    Where is the reading done relative to the spinning magnet axis, which way is the magnet spun relative to the n-s poles and how is the magnet spun (ie, is it a bar magnet tapped to something spinning or are you measuring an electro-magnet)?

    There are lots of interesting results with spinning magnets, unusual but fully explainable.

    Diagram would be very useful. Let us know if you have already figured this out.
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