Pearson Edexcel International GCSE
Physics — Topic 2 Paper 2
Electricity · specification 2.1–2.21
Time allowed: 30 minutes
Total marks: 25
Candidate name:
Centre / class:
Answer all questions. You may use a calculator. Show your working. Standard fuse ratings are $3\,\text{A}$, $5\,\text{A}$ and $13\,\text{A}$.
1
A $6.0\,\text{V}$ battery is connected to resistor P of $3.0\,\Omega$ and resistor Q of $9.0\,\Omega$ in series.
(a) Calculate the current in the circuit.
[2]
(b) Calculate the voltage across resistor Q.
[2]
(c) The two resistors are now connected in parallel across the same $6.0\,\text{V}$ battery. State the voltage across resistor P and calculate the current through resistor P.
[2]
(Total for Question 1 = 6 marks)
2
A hairdryer is labelled $230\,\text{V}$, $920\,\text{W}$. It has a metal case and an earth wire.
(a) Calculate the current in the hairdryer when it is used on the mains.
[2]
(b) Choose the most appropriate fuse. Explain why a $13\,\text{A}$ fuse would be a poorer choice.
[2]
(c) The hairdryer is used for $8.0\,\text{minutes}$. Calculate the energy transferred.
[2]
(Total for Question 2 = 6 marks)
3
A student investigates the I–V characteristic of a filament lamp.
(a) Give one safety precaution for this practical and one reason for placing the voltmeter in parallel with the lamp.
[2]
(b) The table shows the student’s results.
| Voltage / V | 0 | 2.0 | 4.0 | 6.0 | 8.0 |
|---|---|---|---|---|---|
| Current / A | 0 | 0.40 | 0.60 | 0.72 | 0.80 |
(i) Calculate the resistance of the lamp at $2.0\,\text{V}$ and at $8.0\,\text{V}$.
[3]
(ii) Explain why the resistance of the lamp is not constant.
[2]
(Total for Question 3 = 7 marks)
4
A thermistor is used in a simple series circuit with a $4.5\,\text{V}$ battery to monitor the temperature of a greenhouse.
(a) State what happens to the resistance of the thermistor when the temperature of the greenhouse increases.
[1]
(b) Explain what happens to the current in the circuit as the greenhouse warms up. The battery voltage stays the same.
[2]
(c) In one interval, $2.4\,\text{C}$ of charge passes through the thermistor. Calculate the energy transferred by this charge in the $4.5\,\text{V}$ supply.
[3]
(Total for Question 4 = 6 marks)
END OF PAPER 2