Question

Consider the following circuit. Determine the current flowing in the ammeter having 1Ω internal resistance in series with the 3Ω resistor.

(a) 0.6

(b) 0.7

(c) 0.8

(d) 0.9

I got this question in an international level competition.

The question is from Compensation Theorem topic in division Useful Theorems in Circuit Analysis of Network Theory

Answer 1

The correct choice is (a) 0.6

The explanation: The current flowing in the ammeter having 1Ω internal resistance in series with the 3Ω resistor shown in the circuit is 0.6 A.

Current through 3Ω resistor = 0.67/(7 + (4||6||2)) = 0.08A. Ammeter reading = 0.67 – 0.08 = 0.59 ≅ 0.6A.