On the way home from his math tutoring session this afternoon I got my son a sandwich at the local Subway. Exiting the store my son was startled by a very small child, who having been left alone in a car facing the stores, was amusing himslef by blowing the car’s horn at people passing in front of the car on the sidewalk.
We both jumped, and after getting our car began discussing car horns. My son asked me how a horn and siren work. I started by saying there must be some arrangement where air is being blown across a whistle of some sort when I stopped and realized how lame and inaccurate that answer probably was given modern electronics and the fact that a horn or siren start immediately, which would preclude the use of a driving fan. Plus in my younger days of doing my own oil changing, spark changing and carb cleaning etc, I remember seeing car horns and they are shaped… well like horns, and there was no fan to be seen anywhere.
I told him “I don’t know but I’ll find out.” So what’s the scoop? How do modern horns and sirens work?