# Energy and Voltage in Circuits focus questions for Pearson Edexcel IGCSE Physics

Have a go at these questions. Remember that the specification is the bottom line of what you need to know!

1. s a series circuit or parallel circuit better for domestic lighting? Explain your answer.
2. How does the current in a series circuit change when there is more applied voltage?
3. How does the current change in a series circuit when more components are added?
4. How does current change with voltage for a wire, filament lamp, diode and resistor?
5. How can current change with voltage be investigated experimentally?
6. What happens to the current in a circuit if the resistance changes?
7. Explain how resistance changes with illumination for a light-dependent resistor.
8. Explain how resistance changes with temperature for a thermistor.
9. How can lamps and LEDs be used to indicate the presence of a current in a circuit?
10. Rearrange the equation voltage = current ✕ resistance.
11. What are the units of voltage, current and resistance?
12. What is current the rate of flow of?
13. Explain the equation Q = I × t.
14. Rearrange the above equation in all ways.
15. Copy and complete the following sentence:  electric current in __________ _____________ conductors is a flow of negatively charged _____________.
16. Explain with a branching diagram that current is conserved at a junction in a circuit.
17. What can you say about the voltage across two components connected in parallel?
18. How can you calculate the currents, voltages and resistances of two resistive components connected in a series circuit?
19. Finish of this sentence: voltage is the energy transferred per __________________.
20. Complete this sentence: the volt is a joule per ____________.
21. Consider the equation: energy transferred = charge × voltage. What are the units of energy, charge and voltage? What are the symbols for energy, charge and voltage?
22. Rearrange the above equation all ways.