I know this is a rather basic question, but how do you charge an object? Not a battery, an object. I'm guessing it involves static electricity, but I'm not sure. Some resources I've been reading talk about charging two objects with opposing voltages, and I am trying to figure out how you do it. I think you do it with DC current, but past that, I'm not sure.
Here is the paper I am talking about: http://www.avonhistory.org/school/gravitor.htm