(2) 13V
Current entering at point Q is 2A as it will divide equally.
Hence current through PQ = 2A
and current in branch PQRS = 2A
∴ Current in branch PS = 6/4 A = 1.5 A
∴ Therefore current drawn from cell = (2.0 + 1.5)A = 3.5A
Total resistance in the circuit = 2Ω + 12/7 Ω = 26/7 Ω
Hence emf E = IR = 3.5 x 26/7 = 13V