Three resistors are connected in parallel across a constant potential difference. The supply current is 0.84 A. Two branch currents are 0.26 A and 0.31 A. The third branch is disconnected. What is the new supply current?
0.27 A0.27\ \mathrm{A}0.27 A
0.42 A0.42\ \mathrm{A}0.42 A
0.57 A0.57\ \mathrm{A}0.57 A
0.84 A0.84\ \mathrm{A}0.84 A
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.