Solving a problem in physics section 60 paragraph 29 el

Solving a problem in physics section 60 paragraph 29 el

29. Cross-section of a system of three parallel lines of endless wires with currents I1 = I2 = I and I3 = 2I shown in Fig. 23. The distance between adjacent wires l = 8 cm. On which side and at what distance x from the current I1 on the line aa ´of the magnetic field strength is zero?

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Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)