Pearson Edexcel International GCSE (9–1) · PHYSICS · Section
Safety devices
17 practice questions
Practice questions
1–10 of 17
Question 1
3 marks · Easy
Answer and see the solution →A student is learning how different safety features protect a user of an electrical appliance.
(a)[1 mark]State the purpose of a fuse in an electrical plug.
(b)[1 mark]What happens to the fuse if too much current flows through the circuit?
(c)[1 mark]Explain how this helps keep the user safe.
Question 2
1 mark · Easy
Answer and check →Which part of a UK three-pin plug is made of plastic for safety?
- A.The casing
- B.The live pin
- C.The earth pin
- D.The fuse
Question 3
1 mark · Easy
Answer and see the solution →Name the wire in a plug that carries current away from the appliance and back to the supply.
Question 4
2 marks · Easy
Answer and see the solution →Look at the diagram of a simple mains circuit with a lamp, fuse, and earth wire.
Simplified circuit showing live wire, neutral wire, fuse, lamp, and earth wire. (a)[1 mark]Explain why the earth wire is connected to metal casings.
(b)[1 mark]State what would happen if the live wire inside the appliance touched the metal casing.
Question 5
1 mark · Easy
Answer and see the solution →Why do modern appliances with plastic casings not require an earth wire?
Question 6
2 marks · Easy
Answer and see the solution →A hairdryer is rated at 4 A. The plug contains a 3 A, 5 A and 13 A fuse.
(a)[1 mark]Which fuse is the most suitable to use?
(b)[1 mark]Explain your answer.
Question 7
1 mark · Easy
Answer and see the solution →Give one advantage of a circuit breaker over a fuse.
Question 8
1 mark · Easy
Answer and check →What does double insulation in an electrical appliance mean?
- A.The appliance has two layers of metal casing
- B.Both the live and neutral wires are fused
- C.There are two protective layers of insulation around live parts
- D.It must be earthed for safety
Question 9
1 mark · Normal
Answer and check →Why is the earth wire important in plugs with metal casings?
- A.It carries current to the appliance in normal conditions.
- B.It completes the circuit for the appliance during use.
- C.It provides a safe path for current if the casing becomes live.
- D.It reduces the voltage supplied to the appliance.
Question 10
2 marks · Normal
Answer and see the solution →An electrical appliance has double insulation and does not have an earth wire. Explain why it is safe to use without an earth wire.