Variable Resistors, Light and Temperature Sensors in Voltage Dividers

Variable Resistors in Voltage Dividers

Variable resistors, also known as potentiometers or rheostats, have a resistance that can be changed manually.
In a voltage divider, a variable resistor allows for adjustment of the output voltage.
By changing the resistance of the variable resistor in the voltage divider, the voltage drop across the resistor changes.
The output voltage of a voltage divider circuit can be calculated using the formula Vout = Vin * (R2 / (R1 + R2)), where R1 is the top resistor and R2 is the variable resistor.
Voltage dividers are commonly used in circuits that require adjustable resistance, such as volume controls in audio equipment.

Light sensors, also known as photocells or Light Dependent Resistors (LDRs), have a resistance that changes in response to light levels.
In darkness, an LDR has a high resistance while in light, it has a low resistance.
By incorporating an LDR into a voltage divider, you can create a circuit that reacts to light levels.
The output voltage of a light-sensor voltage divider can be adjusted by changing the light levels shining on the LDR.

Temperature sensors or thermistors change their resistance depending on the ambient temperature.
NTCs (Negative Temperature Coefficient thermistors) decrease their resistance as temperature increases, while PTCs (Positive Temperature Coefficient thermistors) increase their resistance as temperature increases.
By incorporating a temperature sensor into a voltage divider, you can create a circuit that reacts to temperature changes.
The output voltage of a temperature-sensor voltage divider can be adjusted by changing the ambient temperature.
Voltage dividers with temperature sensors are often used in thermostats and temperature monitoring systems.