INVESTIGATING: LEDs and Resistors? Which resistor to choose? How little current can an LED run on?

Hi everyone, I was messing around with a project, and needed a resistor for an LED. It occured to me that actually, there's no specific value for a resistor. It's of course based on how much you want to restrict the current running down a circuit, and this is to stop the LED burning out. This then got me thinking "How much resistance can one get away with?" or "What's the least amount of current that can flow through an LED circuit whith it still working?".

Basically, in any closed loop, the entire voltage gets dropped across the loop, but the amount of current that flows depends on the resistance in the loop (KCL/KVL). With a 5v circuit and a 50,000ohm resistance, the current that flows would be 0.000a. In other words, resistance is so high that practically no current can flow through it. The surprising thing is that LEDs can glow on microamps - which is something I never knew!

In this video I mess about with this stuff.

Видео INVESTIGATING: LEDs and Resistors? Which resistor to choose? How little current can an LED run on? канала Antony Cartwright (Electronics & Code)