Practical Elec WS 1 - Quiz

The diagram shows an unsafe use of an extension cable. What is the electrical hazard?

• The danger of breaking the appliances

• The danger of electric fire through overheating

• The danger of melting the fuses

• The danger of getting electric shock

Electrical equipment should not be used in damp conditions. What is the main hazard?

• The equipment becomes too hot.

• The insulation becomes damaged.

• The fuses keep blowing.

• The risk of an electric shock

Five electrical appliances are connected to the same socket and there is a very large current. Why is this dangerous?

• The fuses blow in the appliances.

• There is a greater risk of an electrical shock.

• There is overheating in each appliance.

• There is overheating in the socket.

Why should the metal casing of an electrical kettle be earthed?

• To complete an electrical circuit

• To prevent the wire from overheating

• To reduce the risk of electric shocks

• To prevent the casing from getting too hot to touch

Why should the metal casing of an electric heater be earthed?

• to complete an electrical circuit.

• to prevent the cable from overheating.

• to reduce the current.

• to prevent the user from getting electric shock.

What is the colour code of the Live, Neutral and Earth wire?

• Brown, Blue, Yellow-green

• Green, Yellow, Red

• Blue, Brown, Yellow-green

• Yellow-green, Brown, Blue

What are the currents in the neutral and earth wires corresponding to a current of 4 A in the “live” wire?

• 4 A, 4 A

• 4 A, 0 A

• 2 A, 2 A

• 0 A, 4 A

A typical 3-pin plug is shown in the diagram below. Which of the following is the correct connection of the three wires in the cables to the terminal a, b, and c?

• Live wire, Neutral wire, Earth wire

• Neutral wire, Earth wire, Live wire

• Earth wire, Neutral wire, Live wire

• Earth wire, Live wire, Neutral wire

When using 3-core wiring (live, neutral, and earth leads), where should the fuse be fitted?

• Only in the live wire.

• Only in the neutral wire.

• Only in the earth wire.

• In either the live or the neutral wire.

The fuse inside a three-pin plug is normally placed on …………….. .

• live pin

• neutral pin

• earth pin

• both live and neutral pins