electricity and circuts

• switch - turn circuit on and off
• thermistor - lets more current flow at high temperatures
• diode - current can only flow in one direction
• charge = current x time
• charge is measured in coulombs
• series circuit - current is the same at all points
• parallel circuit - the current splits between different branches of the circuit
• potential difference is measured with a voltmeter
• current is measure with an ammeter
• resistance is measured in ohms
• voltage = current x resistance
• ammeter is in series
• voltmeter is in parallel
• power = voltage x current
• UK mains electricity supply - 230 v
• direct current - flows in one direction
• alternating current - regularly changes direction and size
• plug - earth wire

  • yellow and green
  • carries current into the ground if there is an issue
  • for safety
  • 0v
• plug - neutral wire

  • blue
  • return path to power station
  • 0v
• plug - live wire

  • brown
  • carries an alternating potential difference from a power station to appliances
  • 230 v