Hi everyone, I'm new to circuits, and was thinking about using a voltage divider circuit to make a very basic "fire alarm." I've attached an image of what I was thinking. The top resistor is a thermistor. I'm having trouble figuring out what this circuit will do. My understanding of the led is that it will not light unless the voltage across it is higher than a set value, say 2 V. If I choose the resistor and thermistor correctly, the voltage across the LED will be below 2 V at room temperature. If I use a hairdryer and increase the temperature, the thermistor's resistance will drop and then at some point the voltage across the LED will exceed its critical value (2 V in my example), and then the LED should turn on. This is where I am confused. When the LED is on, doens't it act like a short circuit? Then the entire voltage drop should be across the thermistor and once again the LED would turn off (since there is no more voltage drop across it). I know this doesn't make sense, but I can't figure out how to think about this. Any guidance would be greatly appreciated!