Two infinite current carrying wires having current I in opposite directions are shown below. Find the magnetic field (in S.I. units) at point P.

Answer :

Solution :

$B=2\times <!--\; \times \; -->\frac{{\mathrm{\mu <!--\; \mu \; -->}}_{0}i}{2\mathrm{\pi <!--\; \pi \; -->}d}=2\times <!--\; \times \; -->\frac{{\mathrm{\mu <!--\; \mu \; -->}}_{0}I}{2\mathrm{\pi <!--\; \pi \; -->}\times <!--\; \times \; -->0.1}=\frac{10{\mathrm{\mu <!--\; \mu \; -->}}_{0}I}{\mathrm{\pi <!--\; \pi \; -->}}$