WEBVTT

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Let's have a discussion on superposition theorem.
If there are several sources of EMFs acting

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simultaneously in an electrical circuit, according
to superposition theorem, EMF of each source

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acts independently of those of other sources,
i.e. as if the other sources of EMF did not

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exist, and the current in any branch of the
network is equal to each source of EMF separately

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All EMFs being taken to zero. This theorem
is only applicable in linear circuits, that

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are circuits consisting of resistances in
which Ohm's law is valid. Here in this circuit

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there are two voltage sources V1 and V2 acting
simultaneously on the circuit. Because of

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these two voltage sources, say current i flows
through the resistance R. Now replace V2 by

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short circuit, keeping V1 at its position
and measure current through the resistance

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R, say it is i1. Then replace V1 by short
circuit, reconnect V2 to its original position

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and measure current through the same resistance
R and say it is i2. Now if we add these two

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currents i1 and i2, we will get the current
which is equal to the current that was actually

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flowing through R when both voltage sources V1
and V2 were acting on the circuit simultaneously

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Thank you