PHYSICISTS! I have a quick van de graff gen question.

[James3shin]

Van De graff generator, with wire attached to ball, at end of wire is a metal plate that is attached to a plastic stand (ground). The Van De will have a limited amount of current b/c the supply of electrons from the metal plate is limited correct? THe metal plate can not draw much from the plastic stand and will thus turn off the generator? Man it's been a while from physics.

 

[40sTheme]

Yes; it is limited; but it really depends on the conditions in the area where the generator is. On a dry day, you can have an entire room statically charged by a Van De Graff.

 

[FoBoT]

you can get high voltage, but only tiny current, yes

 

[James3shin]

is my reasoning correct though? The generators ball can't get enough electrons from the plate and plastic stand.

 

[Minerva]

If things are ideal the charge can get quite strong even if your source spraying the belt is small. Of course at extremely high electrostatic potential the leakage will be greater. A good design (dessicators, equipotential rings, etc.) can really belt it out.

OTOH, more electrons and a faster belt can keep the sparks coming but it's not efficient. Better dielectrics and environmental management will produce the highest discharge energies. It all depends on what you want to do.