Section-C: Comprehension Type
As shown in figure, a thin, flexible wire hangs from point P in a region where there is a uniform, horizontal, magnetic field of magnitude B directed into, and perpendicular to, the plane of the figure. A weight is attached to the bottom of the wire to provide a uniform tension T throughout the wire. (The weight of the wire itself is negligible). When a current I flows from the top to bottom of wire, the wire curves into a circular arc of radius R.
By considering the forces on a small segment of wire that subtends an angle θ, find the radius of curvature of the wire.