Three infinitely long wires, each carrying a current 1 A, are placed such that one end of each wire is at the origin, and, one of these wires is along x-axis, the other along y-axis and the third along z-axis. Magnetic induction at point (-2 m, 0, 0) due to the system of these wires can be expressed as

The magnetic field due to wire placed along x-axis will be zero. The point under consideration is semifinite position of the wires placed along y-axis and z-axts Magnetic field due to wire placed along y-axis B→y=μ0I4πr(k^)  Magnetic field due to wire placed along z-axis B→z=μI4πr(-j^)  Hence net magnetic field B→=μ0I2πr(k^-j^) After substituting the values, we get B→=μ08π(k^-j^)T