Controlling a transistor with a photoresistor

Principle

The students are familiar with the photoresistor as an illumination-dependent resistor, and the use of an npn transistor as a switch. In this experiment, a circuit is examined in which a transistor is triggered by a photoresistor to switch a filament lamp on and off.
The photoresistor and the potentiometer (as adjustable resistance) form a voltage divider from which the steering voltage for the transistor is picked up. The values of the resistance, and therefore of the voltage, are dependent on the illumination of the photoresistance. The photoresistor is placed at different positions in the basic voltage divider in order to realise both light-switching as well as dark-switching without a relay.

Task

How can a transistor be triggered with a photoresistor?

Examine how one can trigger a transistor with a photoresistor and thereby switch a lamp on and off.

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