A technician makes an electrical load to test a 9.0 V power supply. The load uses two identical fixed resistors, each labelled P. The fixed resistors are kept at constant temperature.
The technician first tests one resistor P.
| potential difference across P in V\mathrm{V}V | current through P in A\mathrm{A}A |
|---|---|
| 2.0 | 0.020 |
The load is then assembled as two parallel branches. One branch contains a resistor P and a 200 Ω resistor connected in series. The other branch contains a resistor P and a 350 Ω resistor connected in series. Both branches are connected across the 9.0 V power supply.
Calculate the total current drawn from the power supply.
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.