Moving Charges And Magnetism

Two very long, straight, parallel wires carry steady currents I and 21 respectively. The distance between the wires is d . At a certain instant of time, a point charge $q$ is at a point equidistant from the two wires, in the plane of the wires. Its instantaneous velocity is v perpendicular to this plane. The magnitude of the force due to the magnetic field acting on the charge at this instant is