In a portable air-quality monitor, a current of 0.79 A reaches junction P and divides. One branch carries 0.24 A; the other continues to junction Q. At Q, a further branch joins the continuing current. The combined current then reaches junction R and divides into branches carrying 0.41 A and 0.32 A.
What current does the branch joining at junction Q carry?
0.18 A0.18\ \mathrm{A}0.18 A
0.55 A0.55\ \mathrm{A}0.55 A
0.73 A0.73\ \mathrm{A}0.73 A
0.06 A0.06\ \mathrm{A}0.06 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.