Pearson Edexcel International GCSE (9–1) · PHYSICS · Section
Alternating current and direct current
17 practice questions
Practice questions
1–8 of 8 · Easy
Question 1
1 mark · Easy
Answer and check →Which of these is a feature of an alternating current (a.c.) supply?
- A.The current changes direction repeatedly.
- B.The current only flows in one direction.
- C.The voltage stays constant at all times.
- D.The voltage is provided by a battery.
Question 2
3 marks · Easy
Answer and see the solution →A torch bulb is connected to a battery that supplies a voltage of 4.5 V and a current of 0.2 A.
(a)[1 mark]Calculate the power of the bulb.
(b)[2 marks]The bulb is turned on for 10 minutes. Calculate the total energy transferred.
Question 3
2 marks · Easy
Answer and see the solution →Explain the difference between the voltage graph of an alternating current (a.c.) and a direct current (d.c.) supply.
Question 4
1 mark · Easy
Answer and check →A mobile phone battery provides a current of 1.5 A at a voltage of 3.7 V. Calculate the power supplied by the battery.
Question 5
2 marks · Easy
Answer and see the solution →State whether a solar panel and the mains supply provide direct current (d.c.) or alternating current (a.c.).
Question 6
3 marks · Easy
Answer and see the solution →A small heater is labelled 240 V, 50 W.
(a)[2 marks]Calculate the current in the heater.
(b)[1 mark]The heater is switched on for 3 minutes. Calculate the total energy transferred.
Question 7
1 mark · Easy
Answer and check →Which equation gives the total energy transferred when a current I flows through a potential difference V for a time t?
- A.E = I × V × t
- B.E = V / I × t
- C.E = t / (I × V)
- D.E = V × V × t
Question 8
1 mark · Easy
Answer and see the solution →State the meaning of direct current (d.c.).