LDRs, Thermistors, and Sensing Circuits | GCSE Physics
Sensing components change their resistance based on external conditions like light or heat.
As light intensity increases, what happens to LDR resistance?
What is LDRs, Thermistors, and Sensing Circuits | GCSE Physics?
"Circuits containing components like LDRs or thermistors that change resistance in response to environmental conditions."
What is the unit of electrical resistance?
Misconception: When a circuit is closed, the 'spent' current returns to the battery.
Calculate the charge flow if a 3A current flows for 10 seconds.
Current is the rate of flow of ____.
Light & Heat
LDR (Light Dependent Resistor): Resistance decreases as light intensity increases.
Thermistor: Resistance decreases as temperature increases (for most GCSE types).
LURD: "Light Up, Resistance Down" is a great way to remember LDR behavior.
These components are used in street lights and thermostats.
Exam Trap: Students often flip these. Remember: more energy (light/heat) makes it easier for charge to flow, LOWERING resistance.
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