Question

Two long, straight, parallel wires 24 cm apart carry currents of I1 = 30A and
I2 = 20A in the same direction. Determine the magnetic field in the plane of the two wires at a point halfway between the wires.

Answer 1

The magnitude of magnetic field is given by formula

$B=\frac{µ_{0} ×I_{1}}{πd} - \frac{µ_{0} × I_{2}}{πd} (1)$

where µ₀ is magnetic constant in vacuum

In our case, we have I₁ = 30A, I₂ = 20A, d=24 cm

Using (1) we got

B=1.67×10^-5 T.

Answer

1.67×10^-5 T