Why would you want to run 20,000 Volts through a watermelon? For science, of course. Creator of this video, TheBackyardScientist on YouTube, pumped 20,000 volts into a watermelon with the help of a capacitor. A capacitor can discharge in an instant, unlike batteries that take their sweet time. And this guy’s using a capacitor the size of a dishwasher.
As you can probably guess, TheBackyardScientist makes use of that capacitor quite often, so there are a few videos with things at the receiving end of 20k Volts. The results may not be surprising, but it’s kind of fun to see anyway.