Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Electricity
249 practice questions
Topics covered
Practice questions
131–140 of 249
Question 131
4 marks · Normal
Answer and see the solution →A lamp is connected to a 12 V battery and draws a current of 2.5 A. It is switched on for 4 minutes.
(a)[1 mark]Calculate the power of the lamp.
(b)[3 marks]Calculate the total energy transferred by the lamp in this time. Give your answer in joules.
Question 132
2 marks · Normal
Answer and see the solution →State the main difference between alternating current (a.c.) and direct current (d.c.). Give one example of each.
Question 133
1 mark · Normal
Answer and check →Which device provides direct current (d.c.) only?
- A.Car battery
- B.Household mains supply
- C.Wind turbine generator
- D.Transformer
Question 134
3 marks · Normal
Answer and see the solution →A coffee machine is labelled 900 W, 230 V. Calculate:
(a)[3 marks]The current it draws from the mains when operating normally. Give your answer to 2 decimal places.
Question 135
4 marks · Normal
Answer and see the solution →A mobile phone charger is rated at 5 V and is connected to a current of 0.6 A.
(a)[1 mark]Calculate the power used by the charger.
(b)[3 marks]If the charger is used for 3 hours, calculate the total energy transferred in kilojoules (kJ).
Question 136
3 marks · Normal
Answer and see the solution →The voltage of two electricity supplies, X and Y, was measured over time. The results are given below:
Voltage measurements for supplies X and Y over time. Time (s) Supply X (V) Supply Y (V) 0 0 3 1 3 3 2 0 3 3 -3 3 4 0 3 On the axes below, plot the voltages of X and Y against time (from 0 to 4 s).
Question 137
3 marks · Normal
Answer and see the solution →A 150 W computer monitor runs on a 19 V supply. Calculate the current in the monitor and the total energy transferred if it is used for 2 hours.
(a)[2 marks]Calculate the current. Give your answer to 2 decimal places.
(b)[1 mark]Calculate the energy transferred in kilojoules (kJ).
Question 138
4 marks · Easy
Answer and see the solution →A student wants to use an electric kettle (rated at 1500 W) on a 230 V mains supply. She checks the plug, which is fitted with a 5 A fuse.
(a)[2 marks]Calculate the current taken by the kettle when it is switched on.
(b)[2 marks]Explain whether a 5 A fuse is suitable for this kettle.
Question 139
4 marks · Easy
Answer and see the solution →A student has a lamp that is fitted with a 3 A fuse and is connected to a 230 V mains supply. The lamp casing is made from metal.
(a)[2 marks]Explain why the lamp must be fitted with an earth wire.
(b)[2 marks]The lamp uses a current of 0.4 A. State whether the 3 A fuse is suitable for this lamp, giving a reason for your answer.
Question 140
4 marks · Easy
Answer and see the solution →A fan heater is rated at 2000 W and is connected to a 230 V mains supply. The heater has a plastic casing, with no earth wire.
(a)[2 marks]Calculate the current used by the heater.
(b)[2 marks]Explain why this appliance does not need an earth wire.