Working Principle of LDR. … These devices depend on the light, when light falls on the LDR then the resistance decreases, and increases in the dark. When a LDR is kept in the dark place, its resistance is high and, when the LDR is kept in the light its resistance will decrease.

What kind of sensor is LDR?

What kind of sensor is the LDR Sensor? Explanation: The LDR sensor is a passive sensor since it requires no external supply of voltage in order for it to work. It simply acts as a variable resistor and changes the resistance of itself while light of varying intensity falls on it.

What is LDR darkness sensor?

LDR (Light Dependent Resistor): LDR or Light Dependent Resistor is one of the commonly used light sensors. In this project, we are using an LDR to detect darkness i.e. when the intensity of light decreases.