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Physics/tandem accelerators


experimenting with the 25kV power supply (1.5 mA) i notice a movement in the wires when i switch it on, but it can not be Lorentz Force, so is it just electrostatic attraction to nearby objects?

also please tell me regarding the voltage control you mentioned on the tandem accelerators. you mention it was like a needle? and so this needle was somehow used to regulate the voltage and so that means that on a van da Geraaff i could use the same simplified needle leakage to reduce the voltage of the terminal.

the leakage current has to be more than the input current for this to work as otherwise the input will still keep up the maximum voltage despite the leak; it will be the equivalent of a smaller current van da Geraaff but same voltage otherwise,no?
thank you,

Could be electrostatic, could be a current pulse response as your terminals charge up.  Can't say without seeing it.  Probably electrostatic forces.  They can be quite strong.

As far as voltage control, there's usually a needle assembly on a particle accelerator to make a coronal discharge current in the buffer gas.  For a simple Van de Graaf (correct spelling) generator, see here:

No, not more than the leakage current.  The two are equal in a steady state.  


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Dr. Stephen O. Nelson


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.


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.

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

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