{"id":342,"date":"2023-02-09T12:13:00","date_gmt":"2023-02-09T12:13:00","guid":{"rendered":"https:\/\/miketorr.com\/writer\/?p=342"},"modified":"2023-02-08T19:52:44","modified_gmt":"2023-02-08T19:52:44","slug":"the-pitch-of-speed","status":"publish","type":"post","link":"https:\/\/miketorr.com\/writer\/2023\/02\/09\/the-pitch-of-speed\/","title":{"rendered":"The Pitch of Speed"},"content":{"rendered":"\n

I’ve come up with an idea: Rational Speed.<\/p>\n

It is equal to real speed divided by length of object (along axis of motion).\nThe unit, perhaps a little surprisingly, is Hertz. This is because the two lengths (distance covered in a second and length of moving object) have the same units, and because one is divided by the other they cancel out – and the remaining units are 1\/seconds, which is equivalent to \u201cthings per second\u201d.<\/p>\n

First example: human locomotion<\/h4>\n

If my body is 30cm from front to back (hopefully not too optimistic) and I am jogging at 4 m\/s, my rational speed is just over 13Hz.<\/p>\n

Jumbo Jet<\/h4>\n

Here\u2019s another example. The Boeing 747-8, which I believe is the longest Jumbo Jet, is 76.25m long. Let\u2019s assume it\u2019s flying at Mach 0.8 at an altitude of 30,000 feet (9,144m). At that altitude, Mach 1 is 678.1mph, or 303m\/s. Therefore the speed is 303 x 0.8 = 242m\/s – and the rational speed is 242\/76.25 = 3.17Hz.<\/p>\n

What we can deduce from the above is that, in rational speed terms, I can jog about four times as fast as \u2013 or maybe I could say two octaves higher than<\/em> \u2013 a Jumbo Jet can fly.<\/p>\n

Let’s do some more!<\/p>\n

My car (a Hyundai Kona EV)<\/h4>\n

Length: 4.165m.
\nAt 70mph (31.29m\/s) the rational speed is 7.5Hz.<\/p>\n

My jogging speed is faster than my car, and both of them are faster than a 747. This new perspective is kind of odd!<\/p>\n

Common Swift<\/h4>\n

Maximum speed in level flight is 69.3mph = 31.0m\/s.
\nLength is about 16cm = 0.16m.
\nRational speed = 194Hz (that’s the G below Middle C).<\/p>\n

Peregrine falcon<\/h4>\n

Maximum speed in level flight is 68mph = 30.4m\/s.
\nMaximum speed in a dive is\u2026 wait, let me check again, surely that\u2019s wrong. Nope, it\u2019s right – 242mph (HOLY CRAP!). That\u2019s 108.2m\/s.
\nLength: about 18 inches = 0.46m.
\nRational speed (level flight) = 66Hz.
\nRational speed (dive) = 235Hz (even closer to Middle C – it’s Bb).<\/p>\n

What about a space rocket? Do we count the orbital speed? Once that’s been attained, the power has ceased. However, even if we are counting orbital speed, the rocket is much shorter by the time it reaches it. Strictly speaking, we’d have to examine it just before stage separation for each stage as well, and compare notes!<\/p>\n

Escaping Earth<\/h4>\n

Saturn V, for example, is 101.6m when launched. How long is it at each stage? And how fast was it travelling as it reached the end of that stage? Those are the numbers we want, and I found them, after some effort, on Wikipedia. It\u2019s important to remember to include the Launch Escape System, that little rocket on top of the nose, during the first stage. This is jettisoned after the first engine cutoff and stage separation. The page gives speeds at the end of each stage as well, so I was able to work out the maximum rational speed during each stage. It turns out that the later ones are far higher than the first one, but surprisingly low, due to the rocket\u2019s length (even in the third stage burn).<\/p>\n

Just before main engine cutoff the rational speed is a mere 22.64Hz, which is almost below audio frequency, but by the time the third stage engine cuts off after reaching Earth orbit it\u2019s moving at a hefty 7,793m\/s (17,432mph), but the rational speed is still just 244.29Hz, which is pleasingly close to that of a stooping falcon. Nature and Technology meet to sing this near-unison duet just below Middle C.<\/p>\n

I\u2019ve included a chart below, for information. I really like the idea that moving objects have an associated frequency, and perhaps I can somehow work this into my music. Let\u2019s wait and see.<\/p>\n<\/div>\n\n\n\n

<\/div>\n\n\n\n
\"Table<\/figure>\n","protected":false},"excerpt":{"rendered":"
Continue reading “The Pitch of Speed”<\/span>…<\/a><\/div>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_FSMCFIC_featured_image_caption":"","_FSMCFIC_featured_image_nocaption":"","_FSMCFIC_featured_image_hide":"","_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[37],"tags":[],"class_list":["post-342","post","type-post","status-publish","format-standard","hentry","category-science","entry"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/miketorr.com\/writer\/wp-json\/wp\/v2\/posts\/342","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/miketorr.com\/writer\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/miketorr.com\/writer\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/miketorr.com\/writer\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/miketorr.com\/writer\/wp-json\/wp\/v2\/comments?post=342"}],"version-history":[{"count":7,"href":"https:\/\/miketorr.com\/writer\/wp-json\/wp\/v2\/posts\/342\/revisions"}],"predecessor-version":[{"id":349,"href":"https:\/\/miketorr.com\/writer\/wp-json\/wp\/v2\/posts\/342\/revisions\/349"}],"wp:attachment":[{"href":"https:\/\/miketorr.com\/writer\/wp-json\/wp\/v2\/media?parent=342"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/miketorr.com\/writer\/wp-json\/wp\/v2\/categories?post=342"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/miketorr.com\/writer\/wp-json\/wp\/v2\/tags?post=342"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}