(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A system of spin 1/2 magnet moments with μ = 1*10^-23 Am² are in a magnetic field of 0.2T. At what temperature will 90% of the magnets be aligned parallel to B?

3. The attempt at a solution

I think I have found the relevant equation:

U=-μB(N↑ - N↓)

where U is the magnetic potential energy, μ is the magnetic moment, B is the magnetic field, N↑ is the number of magnets oritentated up and N↓ is the number of magnets orientated down. My questions now are, how do I know which direction is parallel to B and if this equation is relevant, how do I then convert U to temperature?

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# Homework Help: Magnetic moments

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