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When this circuit is built, the LED dims according to how much light is cast on the photoresistor. Why doesn't the LED glow brighter, as it normally would in series with the photoresistor?

Assume that:

i) no light from the LED reaches the LDR (Light Dependent Resistor), i.e. the light source is entirely external to this circuit;

ii) the resistance of the LDR in darkness, Rdark >> R1;

iii) the resistance of the LDR in bright light, Rbright << R1;

iv) the forward drop of the LED Vled = 1.8V

Now, ask the circuit two questions:

a) what happens to the currents flowing in the circuit in darkness?

b) what happens to the currents flowing in the circuit in bright light?

If you can't work it out from that, post back.

:)

Thank you, I figured out what I was missing :)

Well done.

FYI: