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: A '''variable resistor''' can be used to control the [[Electrical Current|current]] passing through a [[circuit]]. If the [[Potential Difference|potential difference]] is constant then the [[Electrical Current|current]] decreases as the [[Electrical Resistance|resistance]] of the '''variable resistor''' increases.
: A '''variable resistor''' can be used to control the [[Potential Difference|potential difference]] of another [[Electrical Component|component]] in [[Series Circuit|series]] with it. If the [[Electrical Resistance|resistance]] of the '''variable resistor''' is increased the [[Potential Difference|potential difference]] across other [[Electrical Component|components]] will decrease.
{| class="wikitable"
|-
|[[File:PotentialDivider1.png|center|200px]]
|[[File:PotentialDivider2.png|center|200px]]
|[[File:PotentialDivider3.png|center|200px]]
|-
| style="height:20px; width:200px; text-align:left;" |In this [[circuit]] the '''variable resistor''' has a [[Electrical Resistance|resistance]] of 0Ω.
The [[Potential Difference|potential difference]] across the fixed [[resistor]] is 6V.
The [[Electrical Current|current]] through this [[circuit]] is given by:
<math>I = \frac{V}{R}</math>
<math>I = \frac{6}{5}</math>
<math>I = 1.2A</math>
| style="height:20px; width:200px; text-align:left;" |In this [[circuit]] the '''variable resistor''' has the same [[Electrical Resistance|resistance]] as the fixed [[resistor]] (5Ω).
The [[Potential Difference|potential difference]] across the fixed [[resistor]] is 3V.
The [[Electrical Current|current]] through this [[circuit]] is given by:
<math>I = \frac{V}{R}</math>
<math>I = \frac{6}{10}</math>
<math>I = 0.6A</math>
| style="height:20px; width:200px; text-align:left;" |In this [[circuit]] the '''variable resistor''' has twice the [[Electrical Resistance|resistance]] of the fixed [[resistor]] (10Ω).
The [[Potential Difference|potential difference]] across the fixed [[resistor]] is 2V.
The [[Electrical Current|current]] through this [[circuit]] is given by:
<math>I = \frac{V}{R}</math>
<math>I = \frac{6}{15}</math>
<math>I = 0.4A</math>
|}