Pearson Edexcel International GCSE (9–1) · PHYSICS · Chapter
Units (Electricity)
87 practice questions
Topics covered
Practice questions
1–10 of 43 · Normal
Question 1
1 mark · Normal
Answer and see the solution →What is the function of the live wire in a domestic mains circuit?
Question 2
1 mark · Normal
Answer and see the solution →State why the casing of a plug is made from plastic.
Question 3
1 mark · Normal
Answer and check →Which device is designed to automatically switch off the circuit if the current becomes too large?
- A.fuse
- B.resistor
- C.circuit breaker
- D.transformer
Question 4
2 marks · Normal
Answer and see the solution →Explain why it is dangerous if the earth wire in a metal-cased appliance is disconnected.
Question 5
3 marks · Normal
Answer and see the solution →A kettle operates at 230 V and is protected by a fuse.
(a)[1 mark]State the correct unit for each of the following: electrical current, electric charge, and electric potential difference.
(b)[2 marks]If the kettle normally draws a current of 8.5 A, which size of fuse should be used: 5 A, 13 A, or 20 A? Explain your answer.
Question 6
2 marks · Normal
Answer and see the solution →Explain how double insulation protects the user of a domestic electrical appliance.
Question 7
4 marks · Normal
Answer and see the solution →A hairdryer is connected to the mains. The diagram shows a simplified circuit with a fuse.
(a)[2 marks]Name two energy transfers that take place when the hairdryer is used.
(b)[2 marks]Explain what happens to the fuse if the heating element develops a short circuit.
Question 8
4 marks · Normal
Answer and see the solution →A hairdryer uses the heating effect of an electric current. The label on the hairdryer states 'Power: 1200 W'.
(a)[2 marks]Explain how the heating effect of current is used in a hairdryer.
(b)[2 marks]Calculate the energy transferred by the hairdryer in 5 minutes of use.
Question 9
3 marks · Normal
Answer and see the solution →Two halogen bulbs are labelled 50 W and 70 W. Both are in use for 20 seconds. The bulbs convert electrical energy into heat and light.
Energy transferred in 20 seconds Bulb Power (W) Time (s) Energy (J) A 50 20 B 70 20 (a)[1 mark]Calculate the energy transferred by bulb A in 20 seconds.
(b)[1 mark]Calculate the energy transferred by bulb B in 20 seconds.
(c)[1 mark]Explain why bulb B is brighter than bulb A.
Question 10
3 marks · Normal
Answer and see the solution →Look at these two electrical appliances:
Appliance Wire material Wire resistance Toaster Nichrome (metal alloy) High Mains cable in wall Copper Low (a)[3 marks]Explain why the heating element in a toaster uses a wire with high resistance, but the wires in a mains cable use low resistance copper.