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Superposition theorem

The response in a particular branch when all the sources are acting simultaneously is equal to the algebraic sum of individual responses by considering one source at one time.


All the voltage sources are eliminated by short circuit and current sources are eliminated by open circuiting. do not disturb any dependent sources.


If there are several sources acting simultaneously in an electrical circuit, then the current through any branch of the circuit is summation of currents which would flow through the branch for each source keeping all other sources dead.



Example:


question

Eliminate the voltage source by Short circuiting and find voltage and current across each branch.
supetposotion 1

Finally voltage and current across each branch is given as :

supetposotion 2

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