Comments on: Ep. 165: Doppler Effect http://www.astronomycast.com/physics/forces/ep-165-doppler-effect/ Take a weekly facts-based journey through the cosmos with Astronomy Cast. Sun, 11 Jul 2010 12:05:12 +0000 http://wordpress.org/?v=2.9.2 hourly 1 By: Stephen Krisocki http://www.astronomycast.com/physics/forces/ep-165-doppler-effect/comment-page-1/#comment-5420 Stephen Krisocki Thu, 31 Dec 2009 03:05:23 +0000 http://www.astronomycast.com/?p=1064#comment-5420 The earth rotates at 1600 kilometers per second? The earth would disintegrate if its day lasted only 25 seconds. You mean 1600 kilometers per HOUR. Otherwise, it's a great podcast. Thanks The earth rotates at 1600 kilometers per second? The earth would disintegrate if its day lasted only 25 seconds. You mean 1600 kilometers per HOUR. Otherwise, it's a great podcast. Thanks

]]> By: Mike Cloutier http://www.astronomycast.com/physics/forces/ep-165-doppler-effect/comment-page-1/#comment-5376 Mike Cloutier Thu, 17 Dec 2009 20:45:44 +0000 http://www.astronomycast.com/?p=1064#comment-5376 Hello. That was an interesting point about the Doppler shift being discovered in the examination of light, not sound, because there wouldn't have been anything like a car (train, maybe) to observe the phenomenon. But, a Doppler shift can be observed in horse racing. Each hoof in a 10-horse race, for example, generates a sound pulse creating an uneven low-frequency but audible and continuous tone that is raised in pitch as the horses approach and lowered after they pass and recede. I estimate the difference would be a semi tone, and noticeable if you pay attention to it and you stand right beside the rail. You can also notice the individual hoof beats of a single horse or a a few in a smaller race become discernibly slower as they pass, but that's not Doppler shift . . . is it? Imagine an entire cavalry advance coming toward you . . . Hello. That was an interesting point about the Doppler shift being discovered in the examination of light, not sound, because there wouldn't have been anything like a car (train, maybe) to observe the phenomenon.

But, a Doppler shift can be observed in horse racing. Each hoof in a 10-horse race, for example, generates a sound pulse creating an uneven low-frequency but audible and continuous tone that is raised in pitch as the horses approach and lowered after they pass and recede. I estimate the difference would be a semi tone, and noticeable if you pay attention to it and you stand right beside the rail.

You can also notice the individual hoof beats of a single horse or a a few in a smaller race become discernibly slower as they pass, but that's not Doppler shift . . . is it?

Imagine an entire cavalry advance coming toward you . . .

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