Series and Parallel Resistances  a Summary
To summarize all that we have just learned:

There are 2 types of circuits.... Series and Parallel.

Series Circuits

Are connected in a straight line, like a chain.

All current remains the same throughout the circuit.
I
_{
Total
}
= I
_{
1
}
=I
_{
2
}
=I
_{
3
}
etc...

There can be many different voltages in a series circuit, as a voltage
drop appears across every resistor.

The total voltage in a series circuit is equal to the sum of all the
individual voltage drops within the circuit.
E
_{
Total
}
= E
_{
1
}
+ E
_{
2
}
+ E
_{
3
}
+ etc...

The total resistance in a series circuit is equal to the sum of all the
individual resistances within the circuit.

The formula for Resistance in Series is:
R
_{
Total
}
= R
_{
1
}
+ R
_{
2
}
+ R
_{
3
}
+ etc...

Parallel Circuits

Are connected allowing multiple paths for current flow.

All voltage remains the same throughout the circuit.
E
_{
Total
}
= E
_{
1
}
=E
_{
2
}
=E
_{
3
}
etc...

There can be many different currents in a parallel circuit, as each leg has
the same voltage, but can have a different resistance.

The total current in a parallel circuit is equal to the sum of all the
individual currents on each leg of the circuit.

The formula for Current in Parallel is:
I
_{
RTotal
}
= I
_{
R1
}
+ I
_{
R2
}
+ I
_{
R3
}
+ etc...

Resistance is found by reciprocating the sum of the reciprocals of the
resistance of the individual branches

The formula for Resistance in Parallel is:
1

1 1 1 1 1
 +  +  +  +  +
R
_{
1
}
R
_{
2
}
R
_{
3
}
R
_{
4
}
R
_{
X...
}

Ohm's Law states that there is a relationship which exists between current,
resistance, and voltage, such that
E = I x R
