
Here, the magnetic fields produced by the two wires will be perpendicular to one another.
Magnetic field due to wire carrying current 8A is B1=2πdμ0i1
and magnetic field due to wire carrying current 15A is B2=2πdμ0i2
The net magnetic field is
Bnet=B12+B22=2πdμ0i12+i22
=2π×(27)×10−24π×10−7×82+152(d=27cm)
=68×10−6T.