Mains Flashcards
What is direct current
A current which only flows in one direction
What is alternating current
A current which regularly changes direction
Features of a plug
Live wire - Copper wire coated with brown plastic which the current enters the device
Fuse - A ceramic or glass canister which melts if the current is too hot
Neutral Wire - Copper wire coated in blue plastic which connects to the cable and completes circuit
Earth Wire - Copper wire coated in striped plastic which allows the current to flow down to the ground if there is a fault
Why are copper and plastic used in plugs
Copper wires are good conductors and plastic is a good insulator
What is the importance of the fuse
The fuse acts as a fail-safe, once it melts, the circuit is broken and no more current flows, meaning the risk of electrocution is gone
What is the national grid
It connects power stations to houses, workplaces and public buildings across the country
What are transformers
Electrical devices which change the current and voltage of transmission lines
