1. The problem statement, all variables and given/known data What is the emf of the battery shown? there is an external resistance of 2.50 ohm and 4.0 A....The battery has an internal resistance of 0.50ohm 2. Relevant equations V=Ir V= E +/- IR 3. The attempt at a solution Since the current is going away the battery then i use the equation V= E - Ir To find the V of the whole battery V= IR, V=(4)(2.5) = 10V E= V + Ir E= 10 + (4)(0.5) = 12 V please check see if its right. If im not clear i can upload a picture.