Magnetic Field near a curving infinite wire in 3d space

AI Thread Summary
The discussion revolves around calculating the magnetic field at the point (0,0,1) due to a three-dimensional infinite wire carrying current I0. Participants suggest using the equation |B| = μ0I/2πr for long wire segments and integrating the Biot-Savart law for shorter sections. It's emphasized that the magnetic fields from each segment should be calculated individually and then combined. One user expresses uncertainty about adapting the formula for the specific wire configuration, but later confirms they found a solution with classmates. The conversation highlights the importance of understanding both the general formula and the application of the Biot-Savart law in this context.
speedofdark8
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Homework Statement



Problem as given: A three-dimensional wire of infinite length carries a current I0 starting at (-∞,0,0) along a straight line to (0,0,0), bending and traveling along a straight line to (0,1,0), then bending and traveling to (0,1,1) and finally bending and traveling out to (∞,1,1). Determine the magnetic field at (0,0,1).

Homework Equations



Possibly using |B| = μ0I/2∏r ? Not sure whether/how to combine the fields of the different segments using this general formula for the B-field of a current carrying wire.

The Attempt at a Solution



I haven't seen a problem like this in our class, so I'm mostly fishing for a start. I am aware of finding the magnetic B field of a current carrying wire using the equation above, but we never talked about a wire oriented in space with coordinates as such. To start, I would assume the wire is bent at a 90 degree angle at each given point where applicable, find the magnetic field of each segment, and from there I am not too sure where to go.
 
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hi speedofdark8! welcome to pf! :smile:
speedofdark8 said:
A three-dimensional wire of infinite length carries a current I0 starting at (-∞,0,0) along a straight line to (0,0,0), bending and traveling along a straight line to (0,1,0), then bending and traveling to (0,1,1) and finally bending and traveling out to (∞,1,1). Determine the magnetic field at (0,0,1).

Possibly using |B| = μ0I/2∏r ? Not sure whether/how to combine the fields of the different segments using this general formula for the B-field of a current carrying wire.

yes, find the individual fields, and add them :wink:

integrate the Biot-Savart law for the short sections

(you can probably see how to get it from B = μoI/2πr for the long sections)
 
I am not familiar with the Biot Savart Law. For the other sections though, would I be correct with the equation I posted earlier?
 
Thank you for the replys. I have since gotten together with some classmates and we found a solution.
 
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