The UK has plugs, well every country has plugs but the ones in the UK have three pins.
The pins are made out of brass since it is a__ good conductor__ of electricity and won’t rust.
The outside of the plug is made out of plastic since plastic is a good insulator and prevents electric shocks.
Within the plug there are a number of different components, let’s discuss each one with its use.
- Live wire - brown - this carries the alternating potential difference from the supply.
- Neutral wire - blue - this completes the circuit, taking the current back to the source.
- Earth wire - green and yellow stripes - this is a safety wire to stop the appliance becoming live. If there is an electrical fault the earth wire will carry the current into the earth and prevents the current from entering a human person and harming them.
The fuse is also a safety device. Inside a fuse is a small thin wire. If the current gets to high, it will heat up the wire which will cause it to melt __and __break the circuit. In the event of this happening, the fuse has to be replaced before the plug will work again.
There is a danger if the live __and __earth wire are connected since there is a large potential difference between them (230V in the UK). This can cause a spark of electric shock is someone is too close.
Every appliance comes with a power rating in Watts. Recall that power is the rate of energy transfer over time. This means that the higher the rating the more energy is transferred.
- What colour is the live wire?
- What colour is the neutral wire
- What colour is the earth wire?
- Your answer should include: green / yellow
- What is the frequency of the UK mains electricity supply?
- Your answer should include: 50Hz / 50 Hz
- Why are the plug pins made out of brass?
- Your answer should include: good conductor / does not rust /