Question

In the following circuit. Find the current through 4Ω resistor using Millman’s Theorem.

(a) 0.5

(b) 1

(c) 1.5

(d) 2

I got this question during an interview for a job.

This key question is from Millman’s Theorem topic in portion Useful Theorems in Circuit Analysis of Network Theory

Answer 1

Right answer is (c) 1.5

For explanation I would say: V^‘=((V1G1+V2G2))/(G1+G2)=(5(1/1)+10(1/3))/(1/1+1/3)=6.25V. R’=1/((G1+G2))=1/(1/1+1/3)=0.75Ω. I=6.25/(4+0.75)=1.5A.