Consider the current loop in the figure below.(adsbygoogle = window.adsbygoogle || []).push({});

Figure: http://east.ilrn.com/graphing/bca/user/appletImage?dbid=1450953670 [Broken]

Determine the magnetic field (in terms of a, I and d) at the origin.

So I will use mu as the permeability of free space. Since the two vertical wires have opposite directions in current they cancel out, right? If so, then all I have to calculate is the horizontal wire. Well...I use the biot-savart law, but can't seem to get the correct answer. My answer is ((mu*I)/(4*pi*d))*(2*cos(pi/4)). Did I apply the law wrong or am I just totally wrong?

Any help would be great, Thx!

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# Homework Help: Need help on sources of magnetic fields

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