A highly conucting ring of radius `R` is perpendicular to and concentric with the axis of a long solenoid as shown in fig. the ring has a narrow gap of width `d` in its circumference. The solenoid has cross sectional area `A` and a uniform internal field of magnitude `B_(0)`. Now beginning at `t=0`, the solenoid current is steadily increased to so that the field magnitude at any time `t` is given by `B(t)=B_(0)+alphat` where `alphagt0`. Assuming that no charge can flow across the gap, the end of ring which has excess of positive charge and the magnitude of induced e.m.f. in the ring are respectively