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Superposition theorem
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Response is sum of responses from each source alone.
In a linear circuit the response is the sum of the responses to each independent source acting alone with the others zeroed.
Two batteries in a network: find each contribution and add.
Not applicable to power calculations directly.
In more detail
The superposition theorem states that in a linear circuit with several sources, the current or voltage at any point is the sum of the contributions from each source acting alone.
Real-world uses
- Analysing circuits with several batteries.
- Audio mixers apply superposition to signals from multiple inputs.
- Engineers analysing a circuit with two batteries find the current from each battery separately and then add the results.
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Frequently asked questions
How do I switch off a source?
Replace a voltage source with a short circuit and a current source with an open circuit.
Does superposition work for power?
No. Power is proportional to the square of voltage or current, so it does not add directly.
Does superposition apply to power?
No. Power depends on the square of the current, so you must find the total current before calculating power.
Related topics in Current Electricity & Circuits
Maximum power transfer · Thevenin's theorem · Norton's theorem · Delta–star conversion · RC circuit charging · RC circuit discharging