A voltmeter in a circuit

A voltmeter in a circuit measuring potential difference between two points

ZIMSEC O Level Combined Science Notes: Potential difference

  • Potential difference is the “electrical pressure” which causes current to flow in a circuit
  • The amount of current flowing depends on the potential difference of the circuit
  • Potential difference is also known as voltage 
  • It is measured in volts
  • For electrons to flow in a circuit there must be a force to push them
  • The force is provided by the cells
  • The more cells there are the greater the pushing force
  • This force or voltage is measured using a voltmeter
  • A voltmeter measures the potential difference between two points in a circuit
  • It does not measure the potential difference (p.d.) for the whole circuit
  • The voltmeter is thus connected between the two points being measured
  • Voltmeters are thus connected in parallel
  • Ammeters are connected in series
  • If the pushing force in a circuit is increased more electrons should flow through it

To access more topics go to the Combined Science Notes page.