A moving coil galvanometer has a coil with $175$ turns and area $1\mathrm{ }\mathrm{c}{\mathrm{m}}^2.$ It uses a torsion band of torsion constant ${10}^{-6} \mathrm{N} \mathrm{m}/\mathrm{r}\mathrm{a}\mathrm{d}$ The coil is placed in a magnetic field B parallel to its plane. The coil deflects by $1^{\mathrm{o}}$ for a current of $1 \mathrm{m}\mathrm{A}$ The value of B (in tesla) is approximately: