This question already has an answer here:
- accounting for LED resistance 4 answers
I am working on some circuit lab homework this week and am a bit stumped by something I just can't seem to find anywhere in my Circuit Analysis I book.
The lab has me construct the following circuit on my breadboard:
I then mark down the ammeter and voltmeter readings, taking away one resistor each time until down to one. Using this information, my worksheet asks:
When the LED has current flowing through it, a voltage can be seen across it. Thus, the LED will have a resistance. Calculate the resistance of the LED for each of the four cases and record your results in Table III
My first thought is R=V/I. But the result just doesn't seem right to me.
Example data I have measured from this circuit with all 4 resistors: 1.586V, 186.2 microAmps. Using these measurements, the LED has a resistance of 8517.72 Ohms? That can't be right can it?