P5 - Mains electricity Flashcards
What is the voltage of the mains domestic electricity supply?
230 V
How is mains electricity produced?
In generators using EM induction.
Why is AC used instead of DC?
This is where the current alternates. This is easier to generate and simpler to distribute.
How does EM induction work?
A magnet is moved in or near a wire. The coil of wire experiences a changing magnetic field, inducing voltage across the ends of the wire to produce a current in the conductor. This is in a standard generator.
How will the voltage reverse?
If the magnet is turned in the AC generator, or if the magnet is moved out of the coil. If the North-South polarity is reversed this also reverses voltage.
How can the voltage be increased?
Add an iron core, increase speed of rotation, increase the number of turns, or increase magnetic field strength.
