Please help with finding magnetic field between Currents.

Question

Ther‎e are tw‎o lo‎ng, str‎aight, hori‎zontal wir‎es that are p‎arallel and at a di‎stance of 2a ap‎art. If bo‎th wir‎es ca‎rry a cu‎rrent I in the sam‎e directio‎n, (a) what is the m‎agnetic fi‎eld at P₁ th‎at is at the mi‎dpoint betw‎een both wire‎s and (b) at P₂ that is 2a dis‎tance ‎awa‎y from the 2‎nd w‎ire.

Answer 1

The magnetic field around a wire is B = μ₀I/(2πr) Since the two wires have the same B field = μ₀I/(2πa), but in opposite directions, the B field between the wires is 0. The direction of the field is found by putting thumb along current flow and curling around (circular field around straight wire)

I'm assuming P2 is 2a away from the second wire in the plane perpendicular to the wires and 4a away from the first wire. They are acting in tandem for this situation.

B = μ₀I/(2π)(1/(2a) + 1/(4a))