Figure $28-46$ shows a wood cylinder of mass $m=0.250 \mathrm{kg}$ and length $L=0.100 \mathrm{m},$ with $N=10.0$ turns of wire wrapped around it longitudinally, so that the
plane of the wire coil contains the long central axis of the cylinder. The
cylinder is released on a plane inclined at an angle $\theta$ to the horizontal, with the plane of the coil parallel to the incline plane. If there is a vertical uniform magnetic field of magnitude
0.500 $\mathrm{T}$ , what is the least current $i$ through the coil that keeps the cylinder from rolling down the plane?