Question 363 of 403

A potentiometer wire is 100 cm long and a constant potential is maintained across it. Two calls are connected in series first to support one another and then in opposite direction. The balance points are obtained at 50 cm and 10 cm from the positive end of the wire in the two cases. The ratio of the wire in the two cases. The ratio of emf is

(a) 5:4              (b) 3:4

(c) 3:2              (d) 5:1