A four-resistor network is connected to a 9 V battery as shown. Find the magnitude of potential difference between points A and B, in volts.

Question

G1 Physics · Accepted Answer

The two branches have equal total resistance, so the current divides equally. Equivalent resistance of the complete network: Rₑq = 3 Ω Total current supplied by the battery: I = 9/3 = 3 A Therefore current in each branch is Iᵦᵣ = 1.5 A Let the potential of the common left node be V₀. Then, Vₐ = V₀ - (1.5)(2) and Vʙ = V₀ - (1.5)(4) Therefore, Vₐ - Vʙ = [V₀ - 3] - [V₀ - 6] = 3 V Hence the magnitude of the potential difference between A and B is 3 V. Final answer: 3.