Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Electricity
249 practice questions
Topics covered
Practice questions
141–150 of 249
Question 141
4 marks · Easy
Answer and see the solution →A desk lamp is powered by batteries providing direct current (d.c.). A television is powered from the mains (a.c.) supply.
(a)[2 marks]State the difference between the current supplied by batteries and the current supplied by the mains.
(b)[2 marks]Explain why a fuse is used in the plug of the television.
Question 142
4 marks · Normal
Answer and see the solution →A student uses a 230 V electric fan with a power rating of 115 W. The fan's plug contains a fuse, and the outer casing is made of metal.
(a)[2 marks]Calculate the current drawn by the fan to two decimal places.
(b)[2 marks]State the most appropriate size of fuse that should be used in the fan's plug from these options: 3 A, 5 A, 13 A. Explain your answer.
Question 143
5 marks · Normal
Answer and see the solution →A metal-cased toaster and a plastic-cased kettle are shown below.
Appliance features Appliance Casing material Earth wire? Double insulation? Toaster Metal Yes No Kettle Plastic No Yes (a)[3 marks]Explain why the toaster requires an earth wire, but the kettle does not.
(b)[2 marks]State what would happen if the live wire in the toaster became loose and touched the metal case. Explain how the user is protected.
Question 144
4 marks · Normal
Answer and see the solution →A 800 W microwave oven is used in a home where the mains supply is 240 V.
(a)[2 marks]Calculate the current taken by the oven.
(b)[2 marks]The oven is used for 2 minutes. Calculate the total energy transferred by the oven during this time.
Question 145
3 marks · Normal
Answer and see the solution →An electric heater is rated at 2 kW and is connected to a 230 V mains supply. It is used for 30 minutes.
(a)[2 marks]Explain how the heater uses the heating effect of an electric current to warm up a room.
(b)[1 mark]Calculate the total energy transferred by the heater during this time.
Question 146
1 mark · Easy
Answer and see the solution →State what is meant by the term "voltage" in an electric circuit.
Question 147
2 marks · Easy
Answer and see the solution →A current of 2 A flows through a circuit for 10 seconds. Calculate the total charge that passes through the circuit.
Question 148
1 mark · Easy
Answer and check →Which statement correctly describes what happens to the brightness of lamps if more identical lamps are added in parallel to a circuit with one battery?
- A.All lamps become brighter.
- B.All lamps become dimmer.
- C.The brightness stays the same for each lamp.
- D.Only the first lamp lights up.
Question 149
1 mark · Easy
Answer and see the solution →State what kind of charge carriers are responsible for electric current in a metal wire.
Question 150
3 marks · Easy
Answer and see the solution →A circuit is shown below with a 6 V battery and two resistors, R1 = 3 Ω and R2 = 9 Ω, connected in series.
(a)[1 mark]Calculate the total resistance of the circuit.
(b)[1 mark]Calculate the current in the circuit.
(c)[1 mark]Calculate the voltage across resistor R1.