A student investigates how the resistance of a Light Dependent Resistor (LDR) changes with illuminance under a constant potential difference.
The student obtains the following results:
| Illuminance (lux) | Current (mA) | Resistance (kΩ\text{k}\OmegakΩ) |
|---|---|---|
| 10 | 0.50 | 20.0 |
| 20 | 0.80 | 12.5 |
| 40 | 1.25 | 8.0 |
| 80 | 2.00 | 5.0 |
| 160 | 3.20 | 3.1 |
The student writes this conclusion:
'The resistance of the LDR is inversely proportional to the illuminance.'
Comment on the student's conclusion. Use data from Table 1 to support your answer.
59 exam-style questions on Edexcel GCSE Physics 10.2 Resistance. Each one has a worked solution and a mark scheme showing where the marks go.