A student measures the current in a component for different values of potential difference.
Table
| Potential difference (V) | Current (mA) |
|---|---|
| -1.0 | 0 |
| -0.5 | 0 |
| 0 | 0 |
| 0.5 | 0 |
| 0.7 | 20 |
| 0.9 | 80 |
Which component did the student test?
Filament lamp
Fixed resistor
NTC thermistor
Semiconductor diode
42 exam-style questions on OCR GCSE Physics 3.2 Simple circuits, covering 3.2.1 Series and parallel circuits, 3.2.2 Circuit symbols and circuit diagrams, 3.2.3 Current, potential difference and resistance, 3.2.4 Ohm's law, 3.2.5 Ohmic and non-ohmic resistors, 3.2.6 Designing circuits to investigate resistance, 3.2.7 Linear and non-linear circuit components, 3.2.8 Current-potential difference graphs for components, 3.2.9 Resistance in series and parallel, 3.2.10 Series and parallel circuit problems, 3.2.11 Circuits for measurement and testing, 3.2.12 Power transfer in circuit devices, and 3.2.13 Energy and power in resistor circuits. Each one has a worked solution and a mark scheme showing where the marks go.