Plug wires & Safety appliances

• Plug socket wires are made of copper
• What colour is the neutral wire?

  Blue and goes on left, Pd is 0V
• What Is the yellow and green wire?

  Earth wire, is a safety feature, Pd is 0v
• What is the brown wire

  The live wire, on right, carries AC from mains supply of 230V at 50 Hz
• Why does the current/electricity go through the neutral /earth wire?

  Because it has a Pd of 0V, the live wire has V of 230 the difference in voltage makes the electricity pass from one to the other.
• Humans also have a potential difference of 0V so if we touch a live wire, we get a shock and die 😍
• What is a fuse?

  A Fuse is a thin piece of wire that melts if a current that's too high passes through, saving the appliance from an electric surge.
• What fuses are there?

  3,5,13,25A
• Down side of fuses

  Can only be used once and has to be replaced.
• What are circuit breakers?

  Similar to fuses, they get tripped if a current gets too high, electromagnetic forces pull on latch breaking electrical contact.
• Upd and downs of circuit breakers

  Good: can be reused

  Bad: £££££
• Double insulators is when an appliance is covered in a plastic casing, it is an insulator and does

  not conduct electricity. Double insulated products don't tend to have earth wire.
• How does earth wire work?

  If the live wire comes loose, the current travels down the earth wire which is connected to a metal plate/water pipe underground , and it dissipates the electricity into the ground.
• Surges cause fires sometimes
• What volts are the neutral and live wire

  neutral wire is 0V and live wires is 230V AC
• What colour are the live, neutral and earth wires

  live- brown

  Neutral- blue

  Earth- green and yellow
• Step up transformers increases the voltage to above 1000V and decreases the current. keeping temperature low and less energy is lost
• Step down transformers lower the voltage back to normal 230 V before going into homes