This circuit is now a Series Circuit, because it has two resistors along the same path. The formula for Series Resistors is: Rtotal = R1 R2 More simply, you add resistors in series to find the Total Resistance. We then apply our formula: V = I * Rtotal And solve for any remaining variables. For example, lets say that: V = 6 Volts R1 = 5 Ohms R2 = 7 Ohms I = ? First, we need to add R1 R2 = 5 7 = 12 Ohms So Rtotal = 12 Ohms Use our formula V = I * R, with R being our Rtotal 6 = I * 12 I = 0.5 Amps Now, find the current when: V = 12 Volts R1 = 7 Ohms R2 = 23 Ohms I =