What's That Sound?

Dec 07, 2021

This is a non-mathematical puzzler. In fact, I'm not so sure what field of endeavor this comes in.

So you're driving in your car and you drive by things like telephone poles. And you hear "Whuuh . . . . whuuh . . . whuuh!"

And if my brother's driving, you hear, "Whuuh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . whuuh." Even that was probably too fast, for my brother's driving!

Here's the question. What are you hearing? When you drive by a telephone pole or some other regularly or irregularly spaced things on the side.

You hear this noise. What is it?



Most of the incorrect answers that we got suggested that what you're hearing is air rushing past the tree. Absolutely wrong!

Because if you look at it in the Einsteinian framework of things, frame of reference, the trees ain't moving. And so if you were standing next to one of those trees, would you hear that noise?

And the answer is no, you would not hear that if you were standing next to one of those trees.

Do you know what you would hear? You'd hear the car going by here. And that's what you hear. When you go by the tree, you hear the noise that your own car is making, bouncing off the tree. So what you hear is the engine, exhaust, the noise of the tires on the road, the wheel bearings, the transmission that is grinding itself into all those little pieces.

For a split second, that sound is bouncing off the utility pole, and that's what you hear.

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