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Q & A: Why does my body affect a compass?

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Most recent answer: 10/15/2016
Q:
I recently found out during training that compasses do not work properly around me. It seems like I alter where it reads out as north. We tried 4 different compasses and just by me getting close to each one I would alter the read out by about 15-25 degrees. What could be the cause of this? I don't have any metal anywhere into body and I wasn't wearing a watch or any jewelry or anything.
- Ags (age 25)
Tampa, FL, USA
A:

Hello Ags,

Wow, a great puzzle!   The answer has to be there is some iron or steel object either on your body or in your body  that will attract the compass needle.   In order to find it you have to search around a bit.   Get a friend and have him, or her, hold a compass at various heights close to your body while you slowly rotate around.   The compass needle should deflect the most when the offending object is close by.    Happy sleuthing.

 

LeeH


(published on 12/24/2013)

Follow-Up #1: Is iron in your blood magnetic?

Q:
erm.. how 'bout the iron in your blood?????????
- mach fiver
A:

Hi Mach,

The iron in your blood is in the protein hemogloblin.  In this form it is non magnetic.

LeeH

That is, it doesn't form a ferromagnet. It is paramagnetic when it's not oxygenated, weakly attracted by magnetic fields. When it's oxygenated it's diamagnetic, weakly repelled by magnetic fields. /mw


(published on 10/15/2016)

Follow-up on this answer.