(2) Mains Electricity Flashcards
What is a fuse/circuit breaker?
They are safety devices that shut off the electricity when the current in them becomes too large.
What three wires are usually there in a main circuit?
The live, neutral and earth wire.
What is the purpose of the earth wire?
To protect you in case the appliance has a fault; it provides a path for the current to escape instead of passing though the user.
What is the voltage most countries use to supply to homes?
220 to 240 volts
How can a current produce heat?
It produces heat when the wire passing through it has a high resistance.
What is the formula for power?
Power= Current x Voltage
What is the formula for energy?
Energy= Power x Time
What is alternating current?
An electric current that reverses its direction many times a second at regular intervals.
What is direct current?
An electric current flowing in one direction only
