Procedure

Circuit Diagram:

Fig.1 : Circuit diagram of experimental set-up for verification of Superposition theorem

1. Connect the circuit as shown in the diagram, keeping the switches open and resistance at their maximum positions.
2. Set S₁ to position "aa" and S₂ to position "cc" respectively which means both the sources are energized. Note down the current I₁, I₂ and I₃ from ammeter A₁, A₂ and A₃.
3. Set S₁ to positions "aa" and S₂ to position "dd" respectively which means the, only 220V source is energized and the terminals of S₂ are shorted. Note down current I_1', I_2' and I_3'from the ammeter A₁, A₂ and A₃.
4. Set S₁ to position "bb" and S₂ to position to "cc" respectively. Which means the, only 110V source is energized and the terminals of S₁ are shorted. Note down current I_1'', I_2'' and I_3'' from the ammeter A1, A2 and A3.
5. Compare I₁, I₂ and I₃ with I_1'+I_1'', I_2'+I_2'' and I_3'+I_3'' taking care of signs properly of verify the theorem.
6. Repeat the step (2) to (6) for five different values of resistance for each three rheostats.