Many analog transducers convert the physical quantity they are measuring into resistance. For example, a Light Dependent Resistor (LDR), as the name implies, is a resistor whose resistance is a function of the amount of light falling on it. There are other transducers too, for example, a thermistor whose resistance is a function of temperature.
We usually use a voltage divider to convert the resistance into a voltage, which can then be read in by Arduino.
Voltage Divider
|
