Which statement describes the current-potential difference graph for a diode?
The current is proportional to the potential difference for positive values only
The current rises steeply for negative values, and is zero for all positive values
The current increases at a decreasing rate as the potential difference increases
The current is zero for negative values, and rises steeply above a small positive value
42 exam-style questions on OCR GCSE Physics 3.2 Simple circuits, covering 3.2.1 Series and parallel circuits, 3.2.2 Circuit symbols and circuit diagrams, 3.2.3 Current, potential difference and resistance, 3.2.4 Ohm's law, 3.2.5 Ohmic and non-ohmic resistors, 3.2.6 Designing circuits to investigate resistance, 3.2.7 Linear and non-linear circuit components, 3.2.8 Current-potential difference graphs for components, 3.2.9 Resistance in series and parallel, 3.2.10 Series and parallel circuit problems, 3.2.11 Circuits for measurement and testing, 3.2.12 Power transfer in circuit devices, and 3.2.13 Energy and power in resistor circuits. Each one has a worked solution and a mark scheme showing where the marks go.