Magnetic force b/w wires of unequal length

[diagopod]

Is there a formula for the force between two parallel wires of non-equal length? Would one just use the length of the shorter of the two wires?

 

[Meir Achuz]

That would only work if the longer wire were very much longer.
You can get the field of the longer, but finite, wire by the usual Biot-Savart integral with finite limits. Then integrate this field over the shorter wire.

 

[diagopod]

That would only work if the longer wire were very much longer.
You can get the field of the longer, but finite, wire by the usual Biot-Savart integral with finite limits. Then integrate this field over the shorter wire.

Thanks, that does makes sense.