Practical Electricity for 4Pure

When a correctly wired plug is used to connect a working device to the mains, which statement is NOT correct?

• The fuse is in the live wire connection to the mains.

• The switch is in the live wire connection to the mains.

• The value of the fuse is just larger than the current.

• There is current in the earth wire.

Which wire produces more heat?

• Thick wire

• Thin wire

• Both equally

Study the circuit below. Which of the points should a fuse be placed?

• A

• B

• C

• D

What will happen when a 240 V, 2 kW electric heater is connected to a mains supply using a plug fitted with a 4 A fuse ?

• the fuse in the plug melt

• the heater works normally

• the heater runs at half power

• the heater burns out

plugging many appliances to one socket may cause..............

• heating up of wires

• fires

• electric over load

• all of the above

Why is it dangerous to overload your electrical socket?

• Your electricity bill will be very large

• You may get a shock when touching the appliances

• The wires may overheat and cause an electrical fire

• A short circuit will occur

Which label points to the Neutral Wire on the diagram?

The earth wire is covered with insulation coloured in ________________.

• blue

• brown

• green and yellow stripes

• water

This is the symbol for a...

An electric heater takes a current of 4 A from a 250 V supply when operating normally. How long would it take the heater to convert 400 000 J of electrical energy?

• 400 s

• 1 000 s

• 1 600 s

• 100 000 s