Question Detail
Question
Calculate the total resistance between the points A and B as shown in the circuit diagram (assuming A is the input, 4Ω and (1Ω || 2Ω) are in series, and this combination is in series with 3Ω to reach B).
Correct Answer
Option C is the correct answer.
Detailed Explanation
First, calculate the equivalent resistance of the parallel combination of 1Ω and 2Ω: Rp = (R1 * R2) / (R1 + R2) = (1Ω * 2Ω) / (1Ω + 2Ω) = 2/3 Ω ≈ 0.67 Ω. Then, the 4Ω resistor is in series with this parallel combination, so Rs1 = 4Ω + 0.67Ω = 4.67Ω. Finally, this 4.67Ω is in series with the 3Ω resistor to reach point B, so the total resistance Rtotal = 4.67Ω + 3Ω = 7.67Ω.
Hint
Identify series and parallel combinations correctly. The circuit structure is 4Ω in series with (1Ω || 2Ω), and this entire block is in series with 3Ω.