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What will be the result?

Can anybody tell me what will be the result of this simple circuit?

Picture of What will be the result?
NachoMahma7 years ago
. It's been a lonnnggg time ago for me, but I think the "something slightly interesting" will be the LED getting brighter as the cap charges. . R is just for limiting current thru the LED and cap.
http://falstad.com/circuit/

The java circuit simulator will open.
File - import

$ 1 5.0E-6 10.391409633455755 50 5.0 50162 272 144 368 144 0 1.0 0.0 0.0w 272 144 272 192 0w 368 144 368 192 0w 272 192 192 192 0r 192 192 192 304 0 100.0w 192 304 272 304 0v 368 304 272 304 0 0 40.0 5.0 0.0c 272 192 368 192 0 5.549999999999999E-4 1.9011007901132215w 368 192 432 192 0w 432 192 432 304 0s 432 304 368 304 0 true false

Now watch out, after the switch closed and re-opened the first time, the result will be different, since the LED will not allow the capacitor to completely discharge; Diods allways need a certain voltage to conduct, and so the capacitor cant discharge completely.
sirajmunir (author)  schorhr7 years ago
Thanks for the website.
VIRON7 years ago
It depends on the values but assuming they are reasonable, the "result" will be the LED lighting up. BUT, something slightly interesting will happen first. Try a 4700 uF cap and a 470 ohm resistor and 9 or 12 volts.