(adsbygoogle = window.adsbygoogle || []).push({}); a) A long wire is bent into shape as shown in the figure without he wire actually tocuhing itself. The radius of the circular sectio nis R. Determine the magnitude and direction of B at the cneter C of the circular section when the cirrent i is as indicated.

Well i think that due to the cirular loop the magnetic field is giuven by

[tex] B = \frac{\mu_{0} i }{4 \pi} \int \frac{ds \cross R}{R^3} [/tex]

since R is perpendicular to ds, and constant valued

[tex] B = \frac{\mu_{0} i }{4 \pi R^2} 2 \pi R = \frac{\mu_{0} i }{2R} [/tex]

This field would point out of the page because of ds cross r.

im not qute sure about the linear part though. Wouldnt some component of the linear part affect the magnetic field at C?

Suppose the circular section of the wire is rotated without ditortion about hte indicated diameter until the plane of the circle is perpendicular to the straight section of the wire. The mangetic dipole moment associated with the circular section is now in the direction of the current in teh straight section of the wire. Determine B at C in this case

I m not quite sure about this at all. For starters teh B field would point left.

The linear part would affect the answer in this one wouldnt it ? WOuld it be the same answer as above minus the B field due to a lone straight wire that is

[tex] B = \frac{\mu_{0} i }{2R} - \frac{\mu_{0} i}{2 \pi R} [/tex]

is this correct? Please advise me on what i may have done wrong.

Thank you for your help!

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# Homework Help: Magnetic Field

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