An electrical test unit connects a component of resistance 15 Ω in series with one resistor selected from a resistor bank. The combination is connected across a 12 V supply.
The test is valid only when the current through the component is between 0.40 A and 0.50 A, inclusive.
| Resistor-bank setting | Resistance in series with the component |
|---|---|
| W | 6.0 Ω |
| X | 9.0 Ω |
| Y | 12 Ω |
| Z | 18 Ω |
Calculate which resistor-bank settings make the test valid.
81 exam-style questions on Edexcel GCSE Physics 10.2 Resistance, covering 10.2.1 Current in a circuit and conservation at junctions, 10.2.2 Resistance and variable resistors, 10.2.3 Series and parallel resistance, 10.2.4 I–V characteristics of components, and 10.2.5 LDRs and thermistors. Each one has a worked solution and a mark scheme showing where the marks go.