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Layden jar questions? And some static electricity questions.?

  1. Nov 20, 2012 #1
    Layden jar questions? :) And some static electricity questions.??

    Hello. I'm making a layden jar and i am kinda changing some details in it. and i want to ask if those will affect anything in the performance and if it's shocks can be lethal..
    http://postimage.org/image/s9xqthylt/ [Broken]
    http://postimage.org/image/z86gd6m41/ [Broken]
    http://postimage.org/image/mi6tdu3jl/ [Broken]
    http://postimage.org/image/egikvxks1/ [Broken]
    http://postimage.org/image/8a7xxpc35/ [Broken]

    The plastic the whole thing is made of is HDPE

    The foil is like 6-5 layers.. the first two are wrinkle free and all have been glued togeather by a glue stick.

    The water is full of salt and WAS hot

    You can see too the upper part of the OLD bottle.

    'd it be better like this. a half? or with the other half of the bottle? and if it is better with the other half?
    how should i combine the two?
    Just give me detailed instructions what should i do next..

    I heard a pvc pipe is great for static electricity. So i got a 60 cm one. 1.5 inches

    I rub it with tissues.. or cotton. And it sometimes develops a large large large charge and sometimes not :( WHY?

    Also i heard the i can charge a layden jar from a tv screen?
    what tv type should it be?
    i have all types

    and the old large box tv.

    And detailed instructions please how should i charge that?

    Thanks. hope i did not annoy you.

    EDIT: What is the length of the sparks i can make from a pvc pipe and from a tv screen?
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Nov 20, 2012 #2


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    Re: Layden jar questions? :) And some static electricity questions.??

    A Leyden Jar is just a capacitor so its voltage depends on the voltage it is charged from.

    Any voltage over 40 volts or so is potentially dangerous, so you need to be cautious about touching high voltage sources.

    A Leyden jar is typically charged from a Wimshurst machine and it can develop a very healthy spark which certainly looks as if it could be lethal.

    The picture tube in a "box" TV is supplied with about 30000 volts which is definitely lethal and you should not attempt to use this supply for anything.

    An estimate of the voltage required to cause a spark is that it takes 30000 volts per centimeter to cause a spark in dry air. So, you can work out spark distances from that.

    I have seen a Van der Graaf generator arcing to its base, which was a spark of about 45 centimeters. But I don't think your Leyden Jar will be able to do that.
  4. Nov 20, 2012 #3
    Re: Layden jar questions? :) And some static electricity questions.??

    Uh. okay. but how could i charge it from a tv?

    And please answer the other questions :)

    Your answer is really appreciated :D
  5. Nov 21, 2012 #4


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    Re: Layden jar questions? :) And some static electricity questions.??

    You could look up "Tribo-electric series".


    That site also has other sparky stuff.

    When you rub two insulators together, if they are different, then the charge depends on where they are on the Triboelectic table.

    Rubbing rabbit fur on ebonite is the classic school experiment. The rabbit's fur ends up positive and the ebonite ends up negative. This apparently works with cat's fur and the cat doesn't have to be dead.

    Repeated rubbing is not necessary as the electrons that were removed from the fur will just be returned to it if you rub again.

    The voltage in a TV set is probably lethal and I have an obligation to keep you safe, so if you don't know where to find this voltage, then you probably shouldn't be playing with it. Sorry about that. :)
  6. Nov 22, 2012 #5


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    Re: Layden jar questions? :) And some static electricity questions.??

    My understanding is that the traditional Leyden Jar did not contain water. The inside of the jar was lined with metal foil and a chain dropped down to contact the metal. But wikipedia relates how the very first efforts used a jar that did contain water. However, I suggest that you omit the water and keep the jar dry, because the presence of moisture is anathema to storage of static charge, and I'd say you need not waste time trying in vain to charge a jar that is wet, even if only on the inside.

    Condensers holding a high voltage can be dangerous, but if you only charge it from rubbing a comb on the cat then you will be safe.
  7. Nov 22, 2012 #6
    Re: Layden jar questions? :) And some static electricity questions.??

    This is only an opinion - but please be careful.
  8. Nov 23, 2012 #7


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    Re: Layden jar questions? :) And some static electricity questions.??

    The 'original' Leyden Jars definitely did contain water in them [but only in the bottom, btw] . That was before people understood how they actually worked.
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