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Q & A: Detecting magnets with a metal detector

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Most recent answer: 09/21/2013
Q:
Why does a metal detector not find a magnet
- stacey (age 20)
Griffith,N.S.W,Australia
A:

Metal detectors rely on eddy currents that are induced in metals by a coil driven by a radio frequency oscillator.   These induced currents in turn produce a small magnetic field that can be sensed.  Metalic magnets made of iron or iron alloyed with neodymium or cobalt have large conductivities and should be easily sensed.   Ceramic-ferrite magnets on the other hand have almost no conductivity and thus won't show up.    You might try an experiment using both types.  Tell us your result.

 

LeeH


(published on 09/21/2013)

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