The cheap Chinese bulb that How diodes, LEDs and solar panels 2 days ago   10:27

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Steve Mould
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Check out Mehdi's video over on ElectroBOOM here:
https://ufl.ae/videow/_rwKo6pQ0ji

These LED bulbs will continue to draw power from the mains indefinitely even once they're switched off and the circuit is broken. But how?!

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Comments 2181 Comments

alan connelly
You wired the on/off switch wrong, your dangerouse with electrical power and wiring.
Shanon Bertin
I now understand why when I plug my laptop cable in the outlet first, it produces a little crack !







Also thanks for giving the idea to create an electro gun (I was just being nerd)






🤫
Robb Cochran
... It looks like a cap to some..., And it could act AS a cap sure... But ... It doesnt. When the HOT and Ground Leads are discomected entirely while the rest if the circuit is in tact... I wish i could respond with the schematic i just drew... :(.
Robb Cochran
Its a Jewel Theif and a really bad Tesla Coil? One Wire with an AC Current Potential (which is connected to the lights Circuitry) ... Directly Next to a Copper/Aluminum Dead Line (also connected to the light directly) reacting to the Build and Collapse of the Electromagnetic feild.. its actually NOT a capacitor reaction... Its an Inductive Reaction... As the LOAD current is Directly connected to One lead of the light... And then the Large Coil (to Neutral or Ground) is Also connected to the light directly... Met half way to GROUND with a SWitch or Air Gap... And AIR is semiconductive which really just determines the extra brightness of the bulb... It would be dimly lit either way... (Air or Vaccum Tube) due to Reluctance and Induction throught the parallel Feilds of the coil of wire... Which is Current Loaded... Tryin to find Ground - even a wire that isn't connected to ground still has an electromagnetic feild... that's what makes those tests lights light up there still an electric field inside of the wire... I could go on and on but its not a CAP ... Sorry
Robb Cochran
Capacitive Inductive reluctance??? Im dumb so...
Em P
do not do this while its life, you can do everything when its not plugged in
Imax Ion
sorry dumb question, can we measure the mass of electrons ??
Dead Elf
Where can we buy the bulbs?
Staycalm2010
I tried brilliant a little while a go in the hope to improve my math skills, but I found it to difficult so i didn't stick with it.
wolfedog99
When I was an electrician I would often find completely disconnected circuits(bare at both ends) with 70v when using a high impedance meter to ground, simply from the capacitive coupling with other circuits that share a conduit. Older analog volt meters don't pick it up because they tend to use a much lower impedance which drains the charge faster than it can build.(low and high here are 100Kohms and 10Mohms) Though I never bothered to calculate or test the actual power consumed, or if a resistor shunt like a bulb would change the power consumed, I'm guessing low milli-amps or micro-amps range testing is needed.
Stamen Stoychev
Came here for therapeutic purposes...
Anuj Kankaria
How will the brightness of the LED be affected with cable length? When the switch is turned off
Tech Things
So, long will it last without getting any extra power?
Isaac Bernath
People with British accents just sounds smarter.. Oh nvm, some are actually freakin brilliant...
Jekabs Karklins
I researched this long time ago and the explanation was different. The reason why lightbulb glows is because switch is mounted only to one wire (b.t.w. in households to neutral by Europe standard) . And because LED requires so little power, the neutral wire, although unplugged, still works as a ground. It is because of the long cable length, which is able to dissipate electric charge carriers in surroundings.
Tristan Ryan
Hell yea dude
a1919akelbo
Its not really acting like a capacitor, it's acting more like a 1:1 transformer, the cabling is so long it produces a small current that usually doesn't light bulbs, but i assume that is a low current light?
finity69x2
And if your friend can't turn off the bulb it's because they switched the neutral instead of the hot wire. I'm an electrician and I get VERY PISSED when I find out that people switch the neutrals. It works (in most cases aside from this) but it's unsafe because no one expects the neutral to be switched. In this case because the hot wire is always connected to the bulb then you get that "capacitive" effect and the light stays on. If you switch the hot like you're supposed to then the hot is disconnected from the bulb and the neutral bleeds off any capacitance in the wire to ground so the light goes off.
dsb electrical david betteridge
like the vids maybe a double pole switch sort it
Top Tunes
Electrons flow from negative to positive not positive to negative
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How diodes, LEDs and solar panels The cheap Chinese bulb that 2 days ago   12:15

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The first 200 people to sign up at https://brilliant.org/stevemould/ will get 20% off an annual subscription that gives you access to the full archive of Daily Problems and every single course.

It looks like I may have been a little off on the explanation. Specifically attributing the movement of charge carriers exclusively to the electric field that build up. Read more about that here:

https://www.quora.com/How-do-solar-cells-work/answer/Sjoerd-Smit-3

Animations by Dom Burgess. His brilliant channel, Every Think, is here:

https://ufl.ae/profile/KSWY000L6PYQGv97CDorQqBG

Part 1 demonstration video is here: https://ufl.ae/videow/6MWAp2iKq0m

Photovoltaic cells and LEDs are both made of diodes. Diodes are designed to allow electricity to flow in one direction only but the way we make them (out of semiconductors) means that can absorb and emit light.

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