Physics A-Level
LDR
What LDR means in Physics A-Level, as defined for AQA, OCR.
Definitions of LDR
Exam boards and our study guides word this term in slightly different ways. Learn the version your board uses.
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Reference: AQA
A component whose resistance falls as light intensity rises, so its output p.d. changes with illumination.
A light-dependent resistor has a resistance that decreases as light intensity increases.
Topics that use LDR
- Potential divider (AQA A-Level)
- Potential dividers (OCR A-Level)
Related terms
- Potential divider
- thermistor
- Effect of loading on a divider output
- Effect of loading on output p.d.
- Sensing and switching applications
- Sensor resistance and physical conditions
- Sensors in potential divider circuits
- Series circuits and p.d. sharing
Using LDR in the exam
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