

Or create an electric turbine and motor with some copper and magnets, then show it to some guy in a bar and say I’m from the future.
IIRC they already had electric motors pretty early after the car was invented. I don’t think the idea is radical enough to prove that you’re from the future.
IMO, scientific knowledge isn’t that useful if you only have a surface-level understanding of how things work. Either way, let’s say you know enough to get a reputation as a genius inventor or something like that, maybe some people would actually believe if you claim that you’re from the future then, but I think there would be more people who just think you’re crazy (or “eccentric” if you’re lucky).