1. The problem statement, all variables and given/known data The circuit shown in Fig. 25.37 contains two batteries, each with an emf and an internal resistance, and two resistors. Find (a) the current in the circuit (magnitude and direction) . . . The circuit is a rectangle with the emfs at the top and bottom sides and the resistors on the left and right sides. The positive side of each emf is towards the left side, so that one creates a current clockwise and the other an opposing one counterclockwise. The resistances are: left, 5.0; right, 9.0; top (internal), 1.6; bottom (internal), 1.4. The emf at the top is 16 and at the bottom 8. 2. Relevant equations V = IR V = E - Ir I = E / (r+R) 3. The attempt at a solution For the formula I = E / (r+R), since the denominator is the sum of all the resistances, I assumed I could sum all the emfs as well (taking sign and direction into account). So I did: I = (16-8) / (1.4+5+1.6+9) = 8/17 I do not know what the correct answer is, but I intuitively feel like this answer is wrong.