Question

Find the value of ‘y’ in the equation –(-1/j6)Va+(1/5+1/j5-1/j6)Vb=y obtained from the following circuit.

(a) (10∠30^o)/5

(b) -(10∠30^o)/5

(c) (5∠30^o)/5

(d) (-5∠30^o)/5

The question was asked during an internship interview.

The above asked question is from Nodal Analysis in portion Steady State AC Analysis of Network Theory

Answer 1

Right choice is (b) -(10∠30^o)/5

The explanation is: We got Ybb=1/5+1/j5-1/j6 and Yab=–(-1/j6). The mutual admittance between node b and a is the sum of the admittances between nodes b and a. I2=-(10∠30^o)/5=y.