In the following video, the positive and negative terminals of a high voltage source are connected to two slightly separated metal plates. In-between the plates is a ball coated in conductive paint and suspended by wire.
When the source is turned on and the ball is touched to one of the plates, it becomes statically charged. This repels it from the plate and attracts it towards the other. When it touches the other plate, the charge is transferred and the ball becomes oppositely charged. Then the process is reversed.
However, it would seem that if the ball was connected by a wire to earth, it would be unable to carry the charge as any net accumulation of electrons would sink to earth (like an anti-static device). Is that the right understanding?
Then a follow up question: If that is the right understanding, does that mean a small current flows between the terminal and earth through the ball? That would seem counter intuitive, as you always need a circuit for current to flow.