Potential Divider

A potential divider circuit splits the potential differences up in proportion to their resistances.For a known emf resistances can be carefully chosen to split the voltage and provide a specific value of a potential difference on one component.

V1 V2

=

R1 R2

Vout

=

Vin

×

R2     R1 + R2

Using a variable resistor will give a range of potential differences.The resistor with the higher resistance will have the greater potential difference but there will always be a non-zero potential difference across each component.Using a potentiometer will give a range of values from zero to a maximum.A potentiometer is an electrical component which consists of a coil of fixed length resistance wire with a moveable contact that slides over the wire to adjust the length on either side of the wiper and so adjust the length of the resistance wire in the circuit.