(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Three long parallel wires are 4.0 cm from one another. (Looking along them, they are at three corners of an equilateral triangle.) The current in each wire is 8.00 A, but its direction in wire M is opposite to that in wires N and P. By convention we can say that M is at the top of our equilateral triangle and N on the lower left hand corner.

Determine the magnitude and direction of the magnetic field at the midpoint of the side of the triangle between wire M and wire N.

I'm totally lost; any input would be much appreciated.

2. Relevant equations

B = [tex]\frac{\mu_0 I}{2 \pi r}[/tex]

3. The attempt at a solution

B = [tex]\frac{\mu_0 8}{2 \pi (.0447213595)}[/tex] since the field from M and from N cancel each other out we're left with only the field from P which is [tex]\sqrt{.04^2 + .02^2}[/tex] m from our midpoint of MN. This would give us B = [tex]\frac{2(10^{-7})(8)}{.0447213595} = 3.57770877*10^{-5} T[/tex].

I'm not sure how to calculate the angle although if I do right hand rule for r to B giving me I as out of the page I think that it should be along the plane of the page.

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# Three long parallel wires

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