A wire of length, $l$ carries a current $I$ along the $X$- axis. The magnetic force acting on the wire is given by $\overrightarrow{F}=I{B}_{0}L(\hat{\mathrm{k}}-\hat{\mathrm{j}})\mathrm{T}$ where $B_0$ is a constant. The existing magnetic field $\overrightarrow{B}$ is

What is the net force on the square coil?

A current $i$ is flowing in a conductor as shown in the figure.The magnetic induction at point $O$ will be

The magnetic field at the centre ${}^{\text{'}}O^{\text{'}}$ in the given figure is