This comparison covers Summary Comparison Table within I-V Characteristics for GCSE Physics. Revise I-V Characteristics in Extra Topics for GCSE Physics with 13 exam-style questions and 11 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 5 of 12 in this topic. Use this comparison to connect the idea to the wider topic before moving on to questions and flashcards.
⚡ Summary Comparison Table
| Component | I-V Graph Shape | Resistance Behaviour | Ohmic? |
|---|---|---|---|
| Ohmic resistor (at constant temp) | Straight line through origin | Constant | Yes |
| Filament lamp | Curve through origin, flattening at high V | Increases with temperature | No |
| Diode (forward) | Near-zero then sharp upward curve from ~0.6 V | Very high below threshold, then very low | No |
| Diode (reverse) | Flat (virtually no current) | Extremely high (blocks current) | No |
Practice questions for I-V Characteristics
What does an I-V characteristic graph show for a component?
Explain why the I-V graph for a filament lamp is not a straight line.
Quick recall flashcards
What is a diode used for?
Converting AC to DC (rectification), because it only conducts in one direction
What is an ohmic conductor?
A component where current is directly proportional to voltage at constant temperature. The I-V graph is a straight line through the origin