Re: Earth's magnetic field

["Inge H. A. Pettersen" <ingep@online.no>]

I am sorry for this late answer, but here we go:
In my high school students measure the magnitude of
the horizontal component of the earths magnetic field 
by the following procedure:
1. Place a compass inside a coil with the coil pointing
   in the east-west direction (no current !)
2. Apply a small current (with our apparatus 70 mA) to
   the coil so that the compass needle is making 45 
   degrees with the north-south direction. The horizontal
   geomagnetic force should then be equal to the magnetic
   force from the coil.
Typical values we get are 3*10^(-5) T, which is not bad
according to tabulated values.
> Date:          Mon, 6 Oct 1997 14:23:02 +0000
> Reply-to:      phys-l@atlantis.uwf.edu
> From:          Ian Cameron <Ian.Cameron@trinity.edin.sch.uk>
> To:            phys-l@atlantis.uwf.edu
> Subject:       Earth's magnetic field

> I am trying to obtain a numerical value for the strength of the earth's
> magnetic field here in Edinburgh.  Can anyone tell me where to look or who
> to ask
>
> Ian
>
> Ian Cameron
> Principal Teacher of Physics
> Trinity Academy
> Craighall Ave.
> Edinburgh  EH6 4RT
> Scotland
Inge H. A. Pettersen | email  ingep@online.no
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