A moving coil galvanometer has 100 turns and each turn has an area of $2.0 \mathrm{~cm}^2$. The magnetic field produced by the magnet is 0.01 T and the deflection in the coil is 0.05 radian when a current of 10 mA is passed through it. The torsional constant of the suspension wire is $\mathrm{x} \times 10^{-5} \mathrm{~N}-\mathrm{m} / \mathrm{rad}$. The value of x is