Will a current loop precess or align with a magnetic field?

[nonequilibrium]

Hello,

When I have a current loop (macroscopical, but I don't know if that matters) in an external magnetic field such that the loop's magnetic moment vector is not aligned with the magnetic field, I know it'll create a torque on the loop to align it with the B-field. I was wondering: does this torque always imply precession, or will we simply see alignment in real life? Are there extra conditions that need to be specified before you can say if there will be noticeable precession or alignment?

Thank you.

 

[Curl]

It will align in the direction that has the least energy (with the field). It won't keep rotating due to friction, and in an ideal situation it might oscillate but I haven't though about how this motion affects the current in the loop (if it is significant).

 

[nonequilibrium]

How come precession doesn't come into the picture?

 

[granpa]

you need angular momentum to have precession

 

[nonequilibrium]

granpa - exactly, the electrons in the wire?

 

[granpa]

they have very little mass and they move very slowly

 

[nonequilibrium]

Hm, the argument of "very little mass" doesn't seem valid, because they also have "very little charge", but they're massive in numbers. I suppose the "moving very slowl" argument could make sense... (but not sure because the current itself, after all, is not slow, so the mass movement of the charges/masses also isn't slow). But would you then say that a superconducting loop would precess? Because there the charges don't continuously (they never) bump into things and thus should go a lot faster.