Since I can't do any sort of notation on here, I'm going to make some of my own funky symbols.

~ <-- Vector

`  <-- Greek  (ie.  `u = mu ) I'm sorry for spelling any greek letters incorrectly :{

_(x,y,z) <-- Scalar of the vector( ie. V_x = Scalar in the x direction of the Velocity vector.

I hope I can do this now..

~B ( this is the magenetic field )
For a solenoid(I assume this is what you mean by a coily)
~B_x = 1/2 (`u0 * n * I ) * ( b/(sqrt(b^2 + R^2)) + a/(sqrt(a^2 + R^2)) )

a and b are the distances from the field point to either edge of the coil, R is the radius of the coil, and n is the number of turns.  Of course, I is current

`u0 is the permeability of free space.
this is equal to:
4 * pi * 10^-7 N/A^2
or, the units can be T * m / A

From here, I think torque on magnets or `t (tau)
~`t = ~`u x ~B

Note that x is the cross product.
~`u (mu) is the magnetic moment.

I don't know if this has anything to do with what you want.

(Edited by sakurag at 1:40 pm on June 21, 2004)

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