Does plasma maintain a charge when current flows through it?

[TheEllimist]

I've been looking through the internet and so fair I haven't found anything too clear on this. Some articles have said that plasma can be affected by magnetism and can be conductive, but my question is, will it become positively/negatively charged while current is flowing through it, and if it does would it be possible to make a capacitor with one or more plates being made of/holding plasma?

 

[mfb]

It can have a tiny net charge both with and without current flow, but typically those are negligible.

and if it does would it be possible to make a capacitor with one or more plates being made of/holding plasma?

Not with any relevant capacitance.

 

[TheEllimist]

Thanks.

 

[Khashishi]

"can be" suggests that it is only sometimes true. Plasma is always affected by magnetism and is generally very highly conductive. It's hard to have much charge in most plasmas because the ions will rearrange and neutralize the charge, but you do generally have an excess of positive charge near a plasma-wall boundary due to formation of a Langmuir sheath. Normally, we think of a capacitor as something that won't carry DC current, but a plasma is very conductive and will easily sustain a DC current.