LDR used for night light with transistor and resistor

It´s not very useful to automatically switch on additional lamps during daylight. Rather it´s neccessary to turn on the light when its getting dark. That’s why we connected this time the LDR with one end to the ground brick. This will result in a different functionaly, exactly like we want to happen it this time. The resistance value in our LDR-brick decreases with the increasing intensity of ambient light, so the current ow into the base is reduced by help of the voltage divider. The two 100kOhm resistors are high and with the low value of the LDR, in this case, the voltage at the base gets lower than the threshold voltage of 0.7V. Therefore there is no current ow from collector to emitter and the LED is off. Now when less light falls into the LDR, because it getting darker in the environment, the voltage divider at the base tries to increase the voltage at the base. Slightly above 0.7V the current ows into the base (only limited by the two 100kOhm resistors). In this case the LED turns on.