A battery with an emf of 15 V and an internal resistance of 1 is connected to an external circuit consisting of two resistors of 6 and 3 connected in parallel. The terminal voltage of the battery is:

Step-by-step solution

First, find the equivalent resistance R_ eq of the two external resistors connected in parallel: R_ eq = R₁ R₂ R₁ + R₂ = 6 3 6 + 3 = 18 9 = 2 Next, calculate the total current I flowing in the circuit: I = E R_ eq + r = 15 2 + 1 = 15 3 = 5 A Finally, the terminal voltage V of the discharging battery is given by: V = E - Ir V = 15 - (5 1) = 15 - 5 = 10 V Alternatively, the terminal voltage is equal to the potential drop across the equivalent external resistance: V = I R_ eq = 5 2 = 10 V Answer: 10 V