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Question
pvc tube
pvc tube  

needle
needle  
hello, thank you,
please tell me, in an experiment i did i ended up with unexpected results that i can not explain. so the experimental set-up is shown on the many pictures i took of it that should be attached and named appropriately.
it has a 25kV multiplier, running through a amp-meter terminating in one of three ways. the first is a simple needle. second is a house wire, 0.5m length. the third is the wire inside a pvc tube.
the only sharp point is the needle in the other two terminals the wire is capped with a insulative  material at the ends so there is no exposed metal.
as can be seen the amp meter reads a steady reading and is least with the needle at 3 ľA, the wire is at 6 ľA, the wire in the PVC tube is 7.9 ľA.
i do not understand why the wire is more than the needle other than if it is compensating for its bluntness by its large surface area and the PVC tube being even wider is therefore with the most surface area.
i have repeated this many times, changing aspects of it but the results are the same each time. i thought maybe the wire was touching the large PVC pipes and was therefore conducting electricity through the pipes to ground but when i connected the amp-meter's probe directly to the pipes it did not increase the amps. this shows that the current is moving through the wire into the air.
this form of emailing only allows for two images; i have ten. without them the explanation is insufficient. how can i get the 10 images for you to see?
please tell me what you think,
thank you,
Gene

Answer
I see two pictures, both blurry.  I see PVC pipe in both.  There's a lot I can't make out.  Is the positive terminal of your ammeter grounded?  Where exactly does the other terminal go?  Are there sharp ends on it?  Did you thoroughly clean the tube and rinse it with alcohol to get rid of surface currents?  Just the two blurry pictures really don't show it, and your link didn't post.

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Dr. Stephen O. Nelson

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I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.

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I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

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Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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