A coil in the shape of an equilateral triangle of side 10cm lies in vertical plane between the pole pieces of permanent magnet producing a horizontal magnetic field 20 mT. The torque acting on the coil when current of 0.2 A passed through it and its plane becomes parallel to the magnetic field will be $\sqrt{x}\times {10}^{-5}$ Nm , the value of $x$ is ___