A 1.59 m long wire weighing 0.0668 N/m is suspended directly above an infinitely straight wire. The top wire carries a current of 32.4 A and the bottom wire carries a current of 24.5 A. Find the distance of seperation between the wire so that the top wire will be held in place by the magnetic repulsion.(adsbygoogle = window.adsbygoogle || []).push({});

Ok. So the formula that I wanted to use was

F/l = (u x I1 x I2) / (2 x pi x a)

where F/l is 0.0668 N/m

l = 1.59 m

u = 4 x pi e - 7 T.m/A

I1 = 32.4 A

I2 = 24.5 A

a = ?

But this is not a parallel wire question, it's a perpendicular wire question. If I use the formula B = (u x I) / (2 x pi x r) where r is the perpendicular distance to the wire, then will I have to ignore the current of the bottom wire? and I don't have the B.

I'm confused. Can anyone help? Thanks guys.

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# Homework Help: Magnetic Fields

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