parallel or it may consist of parallel circuits connected in series.

You have had the necessary laws and formulas needed to solve series-

parallel circuit problems. The important thing to remember is that

when working with resistances connected in series, use series-circuit

laws; and when working with resistances connected in parallel, use

parallel-circuit laws.

The following formulas are based on the laws of series circuits.

Total resistance equals the sum of the individual resistances.

Rt = R1 + R2 + R3 ....

Current flow is the same across

each resistance.

It = I1 = I2 = I3 ....

Total voltage equals the sum of the

voltage drops across each resistance.

Et = E1 + E2 + E3 ....

The following formulas are based on the laws of parallel

circuits.

Total resistance is determined by the reciprocal method.

1

=

1

+

1

+

1 ....

Rt

R1

R2

R3

Total current is equal to the

sum of the current of each

branch.

It = I1, + I2 + I3 ....

Total voltage is equal to the

voltage of each branch.

Et - E1 = E2 = E3 ....