2
$\begingroup$

For the 2nd time I've had a lightbulb flash on in my hand after removing from the power socket. The first time the overhead light in my hallway was out for a couple of days before I got around to changing it. This was a cfl bulb and after I unscrewed it and was making my way down the ladder it flashed back on in my hand for about 3 seconds and went back out. I decided to put it back in the fixture and it went back to working. It's now approximately 4 months later and again the bulb went out. I unscrewed from the socket, had the tube end in my hand coming down the ladder when it again flashed on briefly and went back out. I tried putting it back in the fixture and again it has gone back to working. I don't know what to make of this as I've been unable to find any explanation as to how this can happen. What could make a disconnected bulb light up in my hand without any power source? Any thoughts?

$\endgroup$
  • 1
    $\begingroup$ CFLs have electronic circuits with capacitors that can hold charge for a while in the white socket part of the bulb. In pavouk.org/hw/lamp/isotronic11w.png you can see that capacitor C4 may hold up to approx. 0.1J in energy, which would be enough to cause a few short flashes. $\endgroup$ – CuriousOne Apr 21 '16 at 1:51
1
$\begingroup$

Flurescent light bulbs are known for the way they light up when subjected to static electricity. Here is a video of an instructor using a Van de Graaff generator to light up an old fashioned fluorescent light. CFLs are just old fashioned fluorescent bulbs bent into a different shape with a DC power supply tacked on.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.