Photocells, transistors, capacitors, and IC regulators Answered
I have some questions regarding transistors and capacitors.
First off, photocells/transistors. Transistors basically amplify an electronic signal, cool. But can someone explain what's going on between the photocell, transistor, and resistors in this instructable? https://www.instructables.com/id/ECEKKC1KLOEP2872KE/
Apparently the PC is high resistance when dark. So is most of the current dissipated in the 100K Ohm resistor in the dark, but a good amount still goes through the 470 Ohm resistor, letting the LED light work? If someone could do the math for I and V across the resistors and PC when light/dark and explain how the transistor comes into play that would be awesome and greatly appreciated.
As for capacitors/IC regulators. I know capacitors basically store charge. How does the capacitor work with the regulator in this instructable https://www.instructables.com/id/S4IX41WFAQDX2ZH/ ?
Does the regulator basically feed the capacitor a certain steady voltage, and the LEDs just draw different voltages as they flash or something like that? Why is a capacitor needed, and could a resistor or something be used instead?
Thanks so much for any help :D