Determining magnetic field around two parallel wires

AI Thread Summary
To determine the net magnetic field around two parallel wires carrying currents in opposite directions, the calculations for points A and B are essential. At point B, the magnetic fields from both wires point into the page, and the user initially calculated the magnetic field but arrived at an incorrect conclusion. The user seeks clarification on their approach, particularly regarding the addition of magnetic fields at point B. The discussion highlights the importance of correctly applying the right-hand rule and understanding the direction of magnetic fields in such configurations. Assistance is requested to resolve the misunderstanding and correctly calculate the magnetic fields at both points.
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Two long, straight wires are separated by 0.12 m. The wires carry currents of 3.5 A in opposite directions, as the drawing indicates.

(a) Find the magnitude of the net magnetic field at the point A.

(b) Find the magnitude of the net magnetic field at the point B.

/Users/ashleyhoward/Documents/21_56.gif

here is what i did
at point b, both wires B field point into the page (because of RHR) so i find the Bfield of each wire using B=((4(pi)x10e-7)x-3.5)/2x.06 =-3.67x10e-5 the other wire is the same mag. only positive because it is in the opposite direction. since both B fields ar in the same direction at point b i would just add the two together and that would give me the B field at that point. but this was incorrect. i would then do the same thing at point a but i wanted to get point b correct first. what have i done wrong
 
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Zz.
 
what do you mean?
 
oh i see what you mean now. i didn't realize there was a homework section
 
...but can anyone help me with this problem
 
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