LDRs and Thermistors

The Light Dependent Resistor, LDR

These electrical components decrease their resistance when the light intensity increases.

LDR: Example

This example asks you to read data from a graph to answer the question.

The Thermistor

Thermistors (thermal resistors) change their resistance with temperature, the hotter it gets the lower the resistance.

Thermistor: Example

In this example you need to read the graph to find the data needed for the equation.

LDRs and Thermistors in Circuits

The reason you should know about these components is because they can be used in sensing circuits, to change what happens if it gets too hot, cold, dark or light.

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