The effects of Temperature on Magnetism

1. Jun 29, 2010

AKam

Hi guys, I have chosen the variation of magnetic field strength under different temperatures for my high school physics experimental investigation. We had a guassmeter at school, however it has had a few problems, and so ive dicided to use a compass. My question is, how do i use the angle of my compass that is created by my magnet, to determine the magnetic field strength of my magnet?. I will keep the distance between the magnet and compass constant in each of my measurements. Please recommend the formulas i need to use . Thanks

I have seen an article regarding magnetic field strength with distance, where formulas such as these were used:
m× (HE +HM) = 0
mHE sin θ = mHM cos θ tan θ =HM/ HE
Can such formulas, be applied to my situation?

2. Jun 29, 2010

AJ Bentley

A very, very long time ago, before electronic gaussmeters were invented and I was still at school, we used to use a compass to measure magnetic fields.

Actually the compass was a rather sophisticated one with a big dial marked off in degrees and with a vernier to make it even more accurate. And we called it a 'magnetometer'.

The basic idea is to balance the rotation of the compass caused by the field you want to measure against a known, standrad field - usually we used the earth's field for that.

I can't remember the techno/mathematical details (its just a case of balancing out opposing forces then using inverse square laws) and I tried googling magnetometer but didn't come up with anything useful on the first page.
I might be able to find more details in one of my old textbooks if you can't find out any more yourself. But I'll give you the time to research it first.

3. Jul 7, 2010

AKam

Thanks for the reply. I've been researching a bit and I've come accross magnetic torque, and magnetic dipole moment. Would these be relevant?