The old and pretty common tail told by parents to their children is something similar to "If you keep switching the light on and off you will start a fire!".

Is this even possible? If so, are there any statistics to back this up? Whats the likelihood of this actually happening? Or is this just a myth?

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    What culture says this? I've never heard of it.
    – Kevin
    Jun 21 '18 at 23:37
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    Welcome to Skeptics! Parents also say your face will stay that way if the wind changes and other tall tales to control the behaviour of kids. Can you please show some notability - that people actually believe the claim. We have a rule that only widely-held beliefs are in scope for this site (or at least, claims made by notable people and organisations that are widely seen).
    – Oddthinking
    Jun 21 '18 at 23:41
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    As a kid I did manage to make a light bulb explode and blow the lighting circuit fuse by flicking it on and off too fast. That did leave an impression but I also don't see how it could lead to a fire unless the exposed wires in the bulb came into contact with something flammable whilst hot enough to ignite it. And this was old incandescent bulbs. Modern LED and CF bulbs don't get as hot in the first place and LEDs don't contain gas. Also bear in mind I live where the mains voltage is 240v as opposed to 110 in America
    – GordonM
    Jun 22 '18 at 10:08
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    Yes in the old days that could happen, because the old light bulb makes light via glowing. A glowing wire has a high resistence while a cold one has way lower resistence. So in the moment you turn the light on you basicly have a short cirquit until the lightbulb gets hot and therefore it's high resistence. When you turn it on and of again repeatedly, it takes way longer for the light to get warm. If have now a lot of lights in parrallel, as everything in the house cirquit is, your wires may take that once a while but not if quick succession. However modern lights like LED or *
    – Etaila
    Jun 22 '18 at 11:16
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    The closest thing I found to this claim in an acceptable source: "Over time, light switches will wear out. When this happens, a small spark on the electrical contacts will be emitted whenever you turn the light on and off. Soon the contacts won’t meet properly, and electricity will flow more freely, creating heat. Again, this is a fire risk. Replacing old light switches is always a good idea."
    – Fizz
    Jun 22 '18 at 20:16

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