Figure shows square current carrying coil of edge length L. The magnetic field on the coil is given by $\overrightarrow{B}=\frac{B_{0}y}{L}\widehat{i}+\frac{B_{0}x}{L}\widehat{j}$ Where  $B_0$ is a positive Constant

 

Resultant force on coil is zero

Equation for the torque  $\overrightarrow{\mu }\times \overrightarrow{B}$ where  $\mu$ is magnetic moment of coil, is not valid here

If coil is free to rotate about y axis torque on the coil is given by  $-\frac{1}{2}iA{B}_0\widehat{j}$

If coil is free to rotate about x axis torque on the coil is given by .$\frac{1}{2}iA{B}_0\widehat{i}$