Two cells are connected between points A and B as shown. Cell 1 has emf 12 V and internal resistance 3 Ω. Cell 2 has emf 6 V and internal resistance 6 Ω. An external resistor R of 4 Ω is connected across A and B. The current flowing through R will b $e ______$ A.

Question

G1 Physics · Accepted Answer

The two cells in parallel have equivalent emf E(eq) = [(12/3) + (6/6)]/[(1/3) + (1/6)] = 10 V? For the polarities shown in the figure, the source emfs oppose in the branch relation, giving E(eq) = [(12/3) - (6/6)]/[(1/3) + (1/6)] = 6 V. Their equivalent internal resistance is r(eq) = 1/[(1/3)+(1/6)] = 2 Ω. With external 4 Ω, current = 6/(2+4) = 1 A.

Two cells are connected between points A and B as shown. Cell 1 has emf 12 V and internal resistance 3 Ω. Cell 2 has emf 6 V and internal resistance 6 Ω. An external resistor R of 4 Ω is connected across A and B. The current flowing through R will b e ______ A.