Electric current created chemically is always ….
Alternating
Large
Direct
What is the mains voltage value in this country?
12 V
115 V
230 V
What is the frequency of mains electricity?
50 Hz
15 Hz
5 Hz
What colour is the live wire?
Green and yellow
Brown
Blue
How much energy is transformed by a 60 W light bulb in 15 minutes?
900 J
54,000 J
4 J
Which is the correct description of the earth wire?
A high resistance path to ground
A low resistance path to ground
A negative resistance path to ground
What is the Earth wire provided for?
If there is a fault, the Earth wire carries away dangerous currents
The Earth wire is needed to make the appliance work
If the Neutral wire fails for some reason, the Earth wire can take over
What is the entire system called that links powers stations and transmission lines to consumers?
Generators
Transformers
The National Grid
A step down transformer …
Lowers the current and lowers the voltage
Increases the current and lowers the voltage
Lowers the current and increases the voltage
What power is transmitted by a 5 A current through a 10 Ω resistor?
50 W
2 W
250 W