Computing the individual currents shows that there is one-half of an ampere

of current through each resistance.

The total current flowing from the

battery to the junction of the resistors, and returning from the resistors

to the battery, is equal to 1 ampere.

The total resistance of the circuit can be calculated using the values of

total voltage (ET) and total current (IT).

Given:

ET = 5 volts

IT = 1 amp

This computation shows the total resistance to be 5 Ohms; one-half the value

of either of the two resistors.

Since the total resistance of a parallel circuit is smaller than any of the

individual resistors, total resistance of a parallel circuit is not the sum

of the individual resistor values, as was the case in a series circuit. The

total resistance of resistors in parallel is also referred to as equivalent

resistance (Req). The terms total resistance and equivalent resistance are

used interchangeably.

There are several methods used to determine the equivalent resistance of

The best method for a given circuit depends on the

number and value of the resistors. For the circuit described above, where

all resistors have the same value, the following simple equation is used: