How Does Current Affect Magnetic Fields in and Around a Wire?

AI Thread Summary
The magnetic field around a long, current-carrying wire can be determined using the Law of Biot-Savart, which states that the magnetic field at a distance r from the wire is given by (μI/2πr). Inside the wire, the magnetic field is influenced by the distribution of current elements, which contribute to the overall field. The discussion emphasizes the need to consider the contributions of current elements on opposite sides of the wire when calculating the magnetic field. Understanding these principles is crucial for accurately determining the magnetic field both inside and outside the wire. This foundational knowledge is essential for further studies in electromagnetism.
Master J
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A long, current carrying wire has a radius R and current I.
What is the magnetic field inside, and outside the wire?


Now, if it asked what is the field a distance r from the wire, I could simply use the Law of Biot & Savart (mu.I/2.pi.r). I havn't dome electricity in a while and I am stuck on this one.

I am sure its simple, I just need a nudge.

Thanks guys.
 
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Where will the current elements be carried on the wire? And as they are in motion consider the current elements on opposite sides of the wire and what their contribution would be to the field within the wire.
 
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