Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Electricity
249 practice questions
Topics covered
Practice questions
91–100 of 249
Question 91
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 92
1 mark · Easy
Answer and see the solution →Why do modern appliances with plastic casings not require an earth wire?
Question 93
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 94
1 mark · Easy
Answer and see the solution →Give one advantage of a circuit breaker over a fuse.
Question 95
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 96
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 97
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.
Question 98
4 marks · Normal
Answer and see the solution →The diagram below shows the inside of a UK mains plug.
Blank diagram of a UK mains plug for labelling (a)[2 marks]On the diagram, identify and label the live, neutral, and earth pins, as well as the fuse.
(b)[2 marks]Describe how the fuse protects the user from electric shock.
Question 99
4 marks · Normal
Answer and see the solution →A student notices that some hairdryers have a plastic casing, while others have a metal casing and an earth wire.
(a)[2 marks]Explain why appliances with a metal casing must be earthed.
(b)[2 marks]Describe how the earth wire and fuse work together to protect the user if a fault occurs inside a metal-cased appliance.
Question 100
1 mark · Normal
Answer and see the solution →Which part of the plug ensures that the user does not get an electric shock if the live wire touches the casing?
- A.The earth wire
- B.The live wire
- C.The neutral wire
- D.The brass pins