Suppose a long rectangular loop o width w is moving along the x -direction with its left arm in magnetic field perpendicular to the plane of the loop (see figure). The resistance of the loop is zero and it has an inductance L . At time, t = 0 , its left arm passes the origin, O . If for t ≥ 0 , the current in the loop is I and the distance of its left arm from the origin is x , then I versus x garph will be