Two long parallel wires in the YZ plane at a distance 2a apart carry a steady current I in opposite directions. Midway between the wires is a rectangular loop of wire of dimensions $2b\times d$ carrying current I as shown in figure (b<a<2b). The loop is free to rotate about the z axis and the currents remain fixed to ‘I’ irrespective of the relative motion between the loop and the wire.

Take a=8cm, b=6cm and d=5cm also let I=1A
Torque tending to rotate the rectangular loop about its axis when the angle between plane of loop and y axis $\varphi =90°$  (i.e., loop is in ZX plane) is $2.4\times x\times {10}^{-7}N-cm.$ Find $x$.