Given,Length = l Magnetic field = BEmf induce in O Q will be equal to OP .And O will be at high potential and P, Q will at low potential V_{OQ} = V_{OQ} = \\dfrac{1}{2} \\omega^2 \\left(\\dfrac{l}{2} \\right) \ herefore V_P = V_Q \ herefore V_{PQ} = O