looked up “how do car horns work” because I was curious and one of the related questions is “do car horns run out of honk” which is endlessly hilarious to me
to those wondering: contemporary car horns
don’t because they’re electric (it’s one of those things where a circuit rapidly switching on and off through a spring-like mechanism creates vibrations in a metal drum which create sound). so long as the battery has charge and the mechanism doesn’t break, they can honk endlessly!
air horns are a different story but most cars don’t have those

