Sunday, 15 February 2026

 

📘 GATE Electrical – Superposition Theorem Advanced Example Problems (With Solutions)

                                                   
Picture used in networks


Superposition Theorem states that in a linear circuit with multiple independent sources, the total response is the algebraic sum of responses due to each source acting alone.

📌 Problem 1 – Two Voltage Sources (Opposite Direction)

A circuit contains: 12V source in series with 4Ω 6V source in opposite direction in series with 8Ω Find current through 4Ω resistor using Superposition.

✔ Step 1: Activate 12V only

Deactivate 6V source → Replace with short circuit.

Total resistance = 4Ω + 8Ω = 12Ω

I₁ = 12 / 12 = 1A

✔ Step 2: Activate 6V only

Deactivate 12V source → Replace with short circuit.

I₂ = 6 / 12 = 0.5A

Direction opposite to I₁.

✔ Step 3: Net Current

I = I₁ − I₂ = 1 − 0.5 = 0.5A

Final Answer: 0.5 A

📌 Problem 2 – Voltage and Current Source Combined

A 5Ω resistor is connected to: 10V voltage source and 2A current source. Find voltage across resistor using superposition.

✔ Step 1: Consider Voltage Source Only

Deactivate current source → Open circuit.

I₁ = 10 / 5 = 2A

V₁ = 10V

✔ Step 2: Consider Current Source Only

Deactivate voltage source → Short circuit.

V₂ = I × R = 2 × 5 = 10V

✔ Step 3: Total Voltage

V = V₁ + V₂ = 10 + 10 = 20V

Final Answer: 20 V

📌 Problem 3 – Power Calculation

A 6Ω resistor connected across: 18V source and 12V source. Find total power dissipated using superposition.

✔ Step 1: 18V Active

I₁ = 18 / 6 = 3A

✔ Step 2: 12V Active

I₂ = 12 / 6 = 2A

✔ Step 3: Total Current

I = 3 + 2 = 5A

Power:

P = I²R = (5)² × 6 = 25 × 6 = 150W

Final Answer: 150 W

🎯 Important Exam Tips

  • ✔ Voltage source → Replace by short when deactivated
  • ✔ Current source → Replace by open when deactivated
  • ✔ Maintain consistent current direction
  • ✔ Add algebraically (consider sign)

Practice Superposition Deeply. It Builds Strong Thevenin & Norton Concepts.

No comments:

Post a Comment

  Operational Amplifiers – Complete Theory Page 15 – Active Low Pass Filter An Active Low Pass Filter allows low-frequency sig...