Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Electricity
249 practice questions
Topics covered
Practice questions
21–30 of 127 · Normal
Question 21
4 marks · Normal
Answer and see the solution →A 12 V battery is connected to a lamp. The current in the lamp is measured as 0.4 A.
(a)[2 marks]Calculate the power supplied to the lamp.
(b)[2 marks]Calculate the energy transferred by the lamp in 2 minutes.
Question 22
1 mark · Normal
Answer and see the solution →State the unit and one symbol used for each of the following: (i) current, (ii) energy transferred.
Question 23
3 marks · Normal
Answer and see the solution →The graph below shows how the voltage changes with time for an alternating current (AC) supply and a direct current (DC) supply.
Voltage versus time for AC and DC supply. (a)[1 mark]Describe the main difference between the two graphs.
(b)[1 mark]State which graph represents the supply from a cell.
(c)[1 mark]Give one reason why the mains supply uses AC rather than DC.
Question 24
3 marks · Normal
Answer and see the solution →An electric heater draws a current of 2.5 A when a voltage of 60 V is applied across it.
(a)[1 mark]State the equation that relates voltage, current and resistance.
(b)[2 marks]Calculate the resistance of the heater. Include units.
Question 25
3 marks · Normal
Answer and see the solution →A lamp in a circuit has a resistance of 15 Ω. The potential difference across the lamp is 6.0 V.
Calculate the current passing through the lamp. Show your working and give the unit.
Question 26
2 marks · Normal
Answer and see the solution →Explain why connecting wires in a circuit are normally assumed to have zero resistance.
Question 27
3 marks · Normal
Answer and see the solution →The diagram below shows a circuit with a battery and two resistors connected in series.
Series circuit with two resistors (a)[1 mark]Calculate the total resistance in the circuit.
(b)[2 marks]Calculate the current in the circuit. Show your working.
Question 28
3 marks · Normal
Answer and see the solution →A student measures the voltage and current across a piece of wire in an experiment. The results are shown in the table.
Current and Voltage for a piece of wire Voltage (V) Current (A) 0.0 0.0 0.5 0.12 1.0 0.25 1.5 0.37 2.0 0.50 On graph paper, plot a graph of current (y-axis) against voltage (x-axis). Draw the best-fit straight line and label both axes with units.
Question 29
1 mark · Normal
Answer and check →What is the unit of electrical resistance?
- A.Ampere
- B.Ohm
- C.Volt
- D.Watt
Question 30
3 marks · Normal
Answer and see the solution →Describe an experiment you could carry out to investigate how the current in a wire changes as the voltage across it increases. Include the circuit used, what you would measure, and how you would present the results.