Can a charged capacitor create detectable static electricity with a pith ball?

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A charged capacitor can create detectable static electricity, but grounding one terminal does not change the charge on the plates, meaning it won't produce a net positive charge that can be detected by a pith ball. While a capacitor can act as a static source, it is not a generator in the traditional sense. The voltage from a charged capacitor could theoretically attract small objects like paper, similar to a charged balloon, but practical demonstrations require very high voltages, which can be dangerous. Achieving these voltages safely at home is challenging and typically involves methods like friction with a plastic comb. High voltages associated with static electricity are often overlooked in everyday situations, such as experiencing sparks when touching metal objects.
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Suppose I first charge a capacitor so that one plate is positively charged and another negatively. Now I remove the charging source and ground only one of the terminals say negative terminal, will there be a net positive charge in the capacitor that can be detected by a pith ball?
Can a capacitor be used as static electricity generator?
 
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deval vyas said:
Suppose I first charge a capacitor so that one plate is positively charged and another negatively. Now I remove the charging source and ground only one of the terminals say negative terminal, will there be a net positive charge in the capacitor that can be detected by a pith ball?
Can a capacitor be used as static electricity generator?
Grounding one of the terminals will have no effect on the charge on the plates, because with the other terminal connected nowhere, charge is unable to enter or leave the capacitor.

A charged capacitor is a static source of electricity, but not a generator.
 
Thanks...So if charged capacitor is source of static electricity, can it move the pith ball or attract small bits of paper like a charged balloon or charged comb does? is it possible to build a electrostatic levitator based on parallel plate capacitor?
 
It's the voltage that is relevant to attracting pieces of paper. In principle, the voltage from a charged capacitor could be used, in place of a charged plastic comb; in practice you won't be able to easily demonstrate this at home because of the high voltage needed, probably a few thousand volts, at least. It is dangerous to try to produce and store voltages of that magnitude, except by techniques such as involving friction on a plastic comb.

It is easy to overlook the high voltages associated with static electricity we experience daily around us. On dry winter's nights my fingertip can discharge a spark over a 0.5 cm air gap when reaching for canned items on the supermarket shelf!
 
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