Pearson Edexcel International GCSE (9–1) · PHYSICS · Chapter
Units (Electricity)
87 practice questions
Topics covered
Practice questions
31–40 of 87
Question 31
3 marks · Normal
Answer and see the solution →Some electrical appliances have double insulation and do not need an earth wire.
(a)[1 mark]Describe what is meant by double insulation.
(b)[2 marks]Explain why double insulated appliances do not need an earth wire.
Question 32
1 mark · Easy
Answer and see the solution →State the unit of energy transferred in an electric circuit.
Question 33
1 mark · Easy
Answer and check →Which of the following best describes direct current (d.c.)?
- A.A current that constantly changes direction and size.
- B.A current that is always in the same direction with a constant value.
- C.A current that is always zero.
- D.A current that reverses direction every second.
Question 34
2 marks · Easy
Answer and see the solution →A small fan operates at a power of 10 W. How much energy does it transfer in 3 minutes?
Question 35
3 marks · Easy
Answer and see the solution →A torch uses a battery to provide electricity to a bulb.
(a)[1 mark]State whether the current from the battery is alternating current (a.c.) or direct current (d.c.).
(b)[2 marks]Give a reason for your answer.
Question 36
2 marks · Easy
Answer and see the solution →A small electric pump transfers 4800 J of energy in 4 minutes. Calculate the power of the pump.
Question 37
2 marks · Easy
Answer and see the solution →A 30 W charger is used for 2 hours.
(a)[2 marks]Calculate the total energy transferred in joules.
Question 38
1 mark · Easy
Answer and check →Which device supplies alternating current (a.c.) in a home?
- A.A torch battery
- B.A solar cell
- C.The mains electricity socket
- D.A chemical cell
Question 39
1 mark · Easy
Answer and see the solution →State the equation linking energy transferred (E), power (P), and time (t) in an electric circuit.
Question 40
4 marks · Normal
Answer and see the solution →A table lamp is rated at 60 W and is connected to a 240 V mains supply.
(a)[2 marks]Calculate the current in the lamp when it is operating at full power.
(b)[2 marks]Calculate the energy transferred if the lamp is left on for 30 minutes.