Mains Electricity

1.

Some cables for electrical appliances only have two wires within them. Which wire is missing from this configuration?

• Earth

• Neutral

• Live

• The red one

2.

What kind of a plug is used to connect electrical appliances to a mains socket in the UK?

• 2-pin plug

• 3-pin plug

• 4-pin plug

• 5-pin plug

3.

What size of fuse would be required for an electrical appliance which has a power rating of 600W and running off UK mains voltage at 230V?

• 1 A

• 2.5 A

• 3 A

• 5 A

4.

Which colour wire is the live wire in a 3-pin plug?

• Blue

• Yellow and green

• Brown

• Red

5.

If an appliance uses mains electricity at 230 V and the service manual for the appliance recommends using a fuse of 13 A, what is the power consumption it can safely use?

• 2020W

• 2550W

• 2990W

• 3520W

6.

What do electrical appliances transfer?

• Chemical energy

• Electrical energy

• Light energy

• Sound energy

7.

What is the main difference between a circuit breaker and a fuse?

• A circuit breaker can be used to control electrical circuits

• A circuit breaker can be reset whilst a fuse needs to be replaced

• A fuse can be reset whilst a circuit breaker needs to be replaced

• A fuse can be used to control electrical circuits

8.

What does the power of an electrical appliance represent?

• The amount of current that passes through the appliance

• The rate at which it transforms energy

• The speed at which it performs a task

• The size of voltage that the appliance uses

9.

Why do some appliances not need an earth wire?

• These appliances do not need an earth wire as they don't use electricity

• They are double insulated so that shocks cannot be caused if the appliance malfunctions

• They have been incorrectly wired

• All appliances need an earth wire, some do not have a neutral wire

10.

Most appliances have their power consumption and potential difference printed on them. Which of the following can be calculated from these values?

• Internal resistance of transformer

• Momentum

• Current

• Work done