What is an LDR ? || How to use it in the circuit.

LDR :-

LDR is light-dependent resistor . It is a kind of variable resistance . It very automatic with respect to light . we can control it`s resistance with the help of light intensity.

It works on the photo-conductivity principle , and it is a passive element of electronics circuit .

Image of an LDR

It is made of a high resistance semiconductor.

Material use to make It ?

It is made from Semiconductor material , Which have most light Sensitive properties.

Mainly most of the LDR made up of Cadmium Sulphide ,(CdS)

VIDEO:-

IT`S RESISTANCE :-

In the time of dark means when LDE in the dark (low light intensity) it show high resistance in Mega ohms .
{so light intensity is inversely proportional to the resistance of LDE.}

And in the time of light means the intensity of light is high , so LDE show very low resistance in the order of ohms only.

UNIT OF LDR :-

It is a kind of resistance so its unit is same as resistance

which is OHM  𝞨 .

USE OF LDR :-

LDR is also a light sensing element in electronics.

* To make night light :-
It is a electric circuit which is made with the help of LDR. This circuit is use as a automatic switch.
When light fall on this circuit it off automatically and when the light intensity decrease on this circuit it on automatically.
[this circuit is works on both directions...]

We can use LDR in any light detecting circuits .
Like Light depending alarm system , Light depending switch , Light depending indicators ect.