# Some light on lightbulbs

**URL:** <https://boards.straightdope.com/t/some-light-on-lightbulbs/53382>\
**Category:** Factual Questions\
**Created:** [February 6, 2001, 6:49pm UTC](https://boards.straightdope.com/t/some-light-on-lightbulbs/53382 "2001-02-06T18:49:00Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![omni-not](https://avatars.discourse-cdn.com/v4/letter/o/8dc957/32.png) [@omni-not](https://boards.straightdope.com/u/omni-not)\
**Post date:** [February 6, 2001, 6:49pm UTC](https://boards.straightdope.com/t/some-light-on-lightbulbs/53382/1 "2001-02-06T18:49:00Z")

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Why is it that some lightbulbs go out with a bang (flash of light) while others go out with a whimper (i.e. you click and there’s no light whatsoever).

And what **does** create that flash of light?

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**Author:** ![Isosleepy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/isosleepy/32/479_2.png) [@Isosleepy](https://boards.straightdope.com/u/Isosleepy)\
**Post date:** [February 6, 2001, 8:47pm UTC](https://boards.straightdope.com/t/some-light-on-lightbulbs/53382/2 "2001-02-06T20:47:24Z")

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Since there’s no answer yet, I should be forgiven a WAG:  
Lightbulbs go out because the filament no longer forms a circuit. If it just doesn’t come on, the circuit was broken after you last turned it off, if you see the bulb go out, you obviously witnessed the event of the circuit being broken. Typically, the circuit is broken because the filament ablated while in operation. (It’s a little thinner every time the lamp burns) Near the end, at one spot, it’s _very_ thin. The thinner the filament, the more resistance for the electrons, the hotter and brighter the filament. Very thin makes for a flash, which also finishes the process of ablation: the filament is “burned out”  
And yes, this oversimplifies things.

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<div class="post-metadata">

**Author:** ![omni-not](https://avatars.discourse-cdn.com/v4/letter/o/8dc957/32.png) [@omni-not](https://boards.straightdope.com/u/omni-not)\
**Post date:** [February 7, 2001, 2:03am UTC](https://boards.straightdope.com/t/some-light-on-lightbulbs/53382/3 "2001-02-07T02:03:00Z")

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> [@](#):
>
> And yes, this oversimplifies things.

Not as far as I’m concerned. Very enlightening. Thanks.