Question

Consider the figure shown below. Find the voltage (V) at node 3.

(a) 4.5

(b) 5.5

(c) 6.5

(d) 7.5

I had been asked this question in semester exam.

This interesting question is from Supernode Analysis in portion Methods of Analyzing Circuits of Network Theory

Answer 1

Correct choice is (a) 4.5

For explanation: Applying Super Node Analysis, the combined equation of node 1 and node 2 is (V1-V3)/3+3+(V2-V3)/1-6+V2/5=0. At node 3, (V3-V1)/3+(V3-V2)/1+V3/2=0. Also  V1-V2=10. On solving above equations, we get V3 = 4.5V.