Voltage across components in a series circuit

  • The supply voltage is shared between components in a series circuit.
  • The sum of the voltages across components in series is equal to the voltage of the supply.
  • The voltages across each of the components in series is in the same proportion as their resistances. This means that if two identical components are connected in series, the supply voltage divides equally across them.

Look at the series circuit below - what are the voltmeter readings at each position when the switch is closed:

1) Position 1: 0 V, 3 V or 6 V

2) Position 2: 0 V, 3 V or 6 V

3) Position 3: 0 V, 3 V or 6 V

A circuit with an open switch at the top left of the main circuit. At the left hand side is a 6 V battery.  A wire circumvents the battery and has a voltmeter Vs labelled 1.  On the bottom of the main circuit are two resistors both 100 ohms.  A wire circumvents the first of these.  This has a voltmeter V1 and is labelled 2.  A wire circumvents the second resistor with a voltmeter V2, labelled 3.

Position 1 = 6 V

Position 2 = 3 V

Position 3 = 3 V