Question

In the circuit given below, the value of voltage VO using Superposition Theorem is _________

(a) −30 – 10IO

(b) 30 + 10IO

(c) −30 + 10IO

(d) +30 – 10IO

The question was posed to me during an interview.

Query is from Advanced Problems on Superposition Theorem topic in division Useful Theorems in Circuit Analysis of Network Theory

Answer 1

Correct answer is (c) −30 + 10IO

Easy explanation: Using Superposition Theorem the voltage VX is given as,

VX = (3-IO) (2||40) + 5VX \(\frac{2}{40+2}\)

Or, VX = \(\frac{80}{42}(3 – I_O) + \frac{10}{42}\)VX

Or, VX = \(\frac{\frac{80}{42}}{1-\frac{10}{42}}\)(3 – IO) = 2.5(3 – IO)

∴ VO = VX – 5VX = −30 + 10IO.