Electricity in the home

• What is happening to Lagos's population?

  It is growing rapidly
• Why has Lagos's population grown over time?

  Due to different reasons at different times
• Who ruled Lagos during colonial times?

  British
• What occurred after Lagos gained independence?

  There was rapid economic development in the area
• What are the two types of electricity supply in homes?

  • Alternating current (a.c.)
  • Direct current (d.c.)
• What is the mains supply voltage in the UK?

  Approximately 230 V
• What is the frequency of the a.c. mains supply?

  50 cycles per second or 50 Hz
• How does the movement of charges in a.c. supplies change?

  It is constantly changing direction
• What produces alternating currents?

  Alternating voltages
• What is the purpose of the neutral wire?

  Completes the circuit when operating normally
• What does the earth wire do?

  Protects the wiring and provides safety
• What color is the live wire?

  Brown
• What color is the neutral wire?

  Blue
• What color is the earth wire?

  Green and yellow
• Why are the colors of wires standardized?

  To easily identify their purposes
• What are the three types of wires in electrical systems?

  1. Live wire (brown)
  2. Neutral wire (blue)
  3. Earth wire (green and yellow)
• What does the live wire carry?

  The voltage supply
• What is the function of the earth wire?

  To prevent electric shock
• What is the purpose of insulation on wires?

  To prevent electric shock and short circuits
• What happens if the insulation on a wire is damaged?

  It can lead to electric shock or fire
• How do the different wire colors help in safety?

  They indicate the function and prevent misuse
• What is the main purpose of the earth wire in a circuit?

  To provide a safe path for current
• Why is it important to have a neutral wire?

  It completes the circuit for current flow
• What does the earth wire color indicate?

  It indicates safety and grounding
• What is the significance of the mains supply voltage?

  It powers household electrical devices
• How do the three types of wires work together in a circuit?

  They ensure safe and effective electricity flow
• What does the neutral wire complete in a circuit?

  The circuit
• When does current flow through the live and neutral wires?

  When the appliance is operating normally
• What is the voltage of the earth wire?

  0 V
• What colors are used for the earth wire?

  Green and yellow
• What is the purpose of the earth wire?

  For safety and protecting the wiring
• What happens if something goes wrong in the circuit?

  The appliance stops becoming live
• What is the p.d. between the live wire and the neutral wire?

  230 V
• What is the p.d. between the live wire and the earth wire?

  230 V
• What happens if there is no p.d. between the live and neutral wires?

  The current isn't flowing
• What is the risk of touching the live wire?

  You could receive an electric shock
• What happens if a plug socket is switched off?

  There is still a risk of electric shock
• What is the danger of a connection between live and neutral wires?

  It can create a fire hazard
• What is the consequence of a low resistance path to earth?

  A large current will flow
• What could happen if the live and neutral wires are connected incorrectly?

  It could result in a dangerous situation