# What is the difference between an parallel circuit and an series circuit?

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• 7 months ago

In series circuits, all the elements (resistors, inductors, etc) have the same current. In parallel circuits, all the elements have the same voltage.

• 7 months ago

Simply put: a parallel circuit has a common voltage across it and a series circuit has a common current through it. The math follows:

Series (common current): o--ww--ww--ww--o each ww = R a resistance. So when there is a voltage V from post to post (o), the common current is i = V/(R + R + R) = 1/3 V/R. i is flowing through each of the three R's.

Parallel (common voltage):

====o====

ww ww ww

====o====

Now where there is a voltage V from post to post, each R has the same V across it. And the current through each R is V/R = i; so that the current for the entire circuit is I = V/R + V/R + V/R = 3i. Same voltage and same resistors, but three times the total current than the series circuit.

Also note, if an R burns out in the series circuit, the circuit is opened; so there will be no current flowing. But if an R burns out on the parallel circuit, current can still flow through the remaining two good R's.