Components: Resistors, LDRs and Thermistors
Special components change their resistance with conditions, such as light for an LDR and temperature for a thermistor.
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Special components change their resistance with conditions, such as light for an LDR and temperature for a thermistor.
- LDR resistance falls as light increases
- Thermistor resistance falls as temperature rises
- Diodes allow current one way only
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Components: Resistors, LDRs and Thermistors?
Within Physics, which covers forces, energy, waves, electricity, magnetism, light and space explained through motion and experiments, this topic explains Components: Resistors, LDRs and Thermistors. Physics topics explain how things move, push, heat up and carry energy, so each one here pairs a definition with a live model you can change.
Check that you can explain Components: Resistors, LDRs and Thermistors in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Components: Resistors, LDRs and Thermistors explains how the physical world behaves, from sport and transport to electricity and medicine.
Components: Resistors, LDRs and Thermistors in detail
A fixed resistor has constant resistance, while a variable resistor can be adjusted to control current. A light-dependent resistor (LDR) has a resistance that falls as light intensity rises, and a thermistor (NTC type) has a resistance that falls as temperature rises.
Placed in a potential divider, LDRs and thermistors give a changing output voltage that can switch on lights at night or trigger a fire alarm. Diodes allow current in only one direction, and LEDs emit light. Circuit symbols and I-V characteristics help identify each component and its behaviour.
How the interactive helps you understand Components: Resistors, LDRs and Thermistors
Watch the circuit in the interactive. Use any sliders or buttons it offers to change the values and see how the circuit responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Components: Resistors, LDRs and Thermistors.
Real-life uses and examples
- Use Components: Resistors, LDRs and Thermistors to make sense of a practical and its results.
- Answer “explain” questions by linking Components: Resistors, LDRs and Thermistors to a clear cause and effect.
- Predict what a ball, car or circuit will do with Components: Resistors, LDRs and Thermistors before you do the calculation.
Common mistakes to avoid
- Mixing up Components: Resistors, LDRs and Thermistors with a related quantity that has different units.
- Forgetting that some quantities, such as force or velocity, also have a direction.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Components: Resistors, LDRs and Thermistors
What is Components: Resistors, LDRs and Thermistors?
Special components change their resistance with conditions, such as light for an LDR and temperature for a thermistor.
What are the most important points about Components: Resistors, LDRs and Thermistors?
The main points are: LDR resistance falls as light increases; Thermistor resistance falls as temperature rises; Diodes allow current one way only.
Why is Components: Resistors, LDRs and Thermistors useful?
Understanding Components: Resistors, LDRs and Thermistors explains how the physical world behaves, from sport and transport to electricity and medicine.
How can I practise Components: Resistors, LDRs and Thermistors?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Components: Resistors, LDRs and Thermistors?
Related topics in Physics include Electromagnets, Generators and Dynamos, Atomic Structure.