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Speed of Sound Is Too Slow For the Olympics
Hugh Pickens "For decades sports-event organizers have placed speakers behind athletes to convey the sound of an actual pistol but they found that even though the noise came through the speakers all at once, athletes continued to wait for the 'real' sound, ignoring the sounds that came through the speakers ever-so-slightly slowing down the farthest athlete from the gun. Now Rebecca Rosen writes that when the Olympic runners take to their positions on the track later this week, they'll crouch on the ground, ears pricked, and wait for the starting beep played by a 'pistol' that's not a pistol at all, but something more akin to an electronic instrument with only one key. The pistol itself is silent."
Read on for a bit more about the difficulties of timing people with superhuman reaction times.
"A conversation with sprinter Michael Johnson at the Sydney Olympics caused Peter Hürzeler of OMEGA Timing to realize that even with speakers, the speed of sound was still slowing down the farthest athletes. Johnson's reaction time, Hurzeler said, 'was 440 thousandths of a second. Normally athletes leave between 130 and 140 thousandths of a second. ... I asked him, why did you have such a bad starting time?' Turned out, Johnson was in the ninth position, and the sound of the gun was reaching him too slowly.
"In addition after a four year developmental process, a new false start detection system is being introduced this year that will abandon movement in exchange for 'measurement' of pound-force against the back block to determine sprinters reaction times. 'We are measuring the time between the starting gun and when the athlete is moving because to leave the starting block they had to push against and this power is very high' says Hurzeler. 'We did a test last year with Asafa Powell and he was pushing 240 kilograms (529 lbs.) [so] as soon as he gives the time to push against the starting block, it means he will like to leave and we are measuring this in thousandths of seconds and if somebody is leaving before one hundredth thousandth of second, it's automatically a recall, it's a false start.' In track every event is timed to 1/10,000th of a second, and Omega takes 2,000 pictures per second from right before the start of a race to its finish, as backup.
"New touch pads, starting blocks, and timers have also been introduced for swimming."
"In addition after a four year developmental process, a new false start detection system is being introduced this year that will abandon movement in exchange for 'measurement' of pound-force against the back block to determine sprinters reaction times. 'We are measuring the time between the starting gun and when the athlete is moving because to leave the starting block they had to push against and this power is very high' says Hurzeler. 'We did a test last year with Asafa Powell and he was pushing 240 kilograms (529 lbs.) [so] as soon as he gives the time to push against the starting block, it means he will like to leave and we are measuring this in thousandths of seconds and if somebody is leaving before one hundredth thousandth of second, it's automatically a recall, it's a false start.' In track every event is timed to 1/10,000th of a second, and Omega takes 2,000 pictures per second from right before the start of a race to its finish, as backup.
"New touch pads, starting blocks, and timers have also been introduced for swimming."
Speed of sound is 330 m/s. That's a kilometer in a third of a second.
That's a kilometer in three seconds.
Please stand clear of the doors, por favor mantenganse alejado de las puertas
Why not just lights? Works for F1.
Because we typically react a bit faster to auditory stimuli.
(around 30-50 ms faster than visual stimuli)
How can I believe you when you tell me what I don't want to hear?
This reminds me of my time in the navy. There was a minimum requirement for everything, including 60 meter sprint. I ran it once, and got clocked in 1/10th of a second to late. Fearing I would have to run 60 meters once more, I protested because the starter gun was at the finish line! The sound would take almost exactly 1/10th of a second to reach the starting line from the finish line, I argued. They had to accept the protest, of course, and I made the requirement exactly.
Appropriate, for once...
You must have been waiting for the sound.
There is no "I disagree" mod for a reason. Flamebait, Troll, and Overrated are not substitutes.
How about placing runners in some kind of human-sized hamster wheels with clutch mechanisms, so that all runners can already be running at top speed for some short period prior to the actual start of the race, at which time all of the clutches are simultaneously disengaged, so all runners start at full their full stride and their full speed at the same time? This would change the dynamics of racing because it would remove reaction time as a competitive element from the race. But what is a race? Is it to see who has the fastest reaction time, or who runs the fastest, or both?
The Admin and the Engineer
Indeed, do you have a source for the 30-50 ms faster figure? My source says 80 ms faster than visual stimuli. Source: "We ran a t-test based on the tabulated average individual reaction times to each stimuli, and established that the mean average individual reaction time to light (0.28005 sec.) was statistically significantly different than the mean average individual reaction time to sound (0.20407 sec.; P-Value= 1.79E-07 .05, the statistical level of significance)." ( http://www.colorado.edu/eeb/courses/1230jbasey/abstracts%202010/37.htm )
Any sufficiently advanced technology is indistinguishable from magic.
There are 8 lanes on a track, each of which are 1.27 meters wide. There are 7 lane widths between a head in lane 1 and a head in lane 8. This works out to 8.89 meters. The speed of sound is 340.29 meter/sec. The leads to a worst case difference of .026 seconds between lane 1 and lane 8. The difference between bronze and gold in the 2008 Olympics Men's 100 Meters is 0.22 seconds. So at first it seems to not be an issue, but the difference between bronze and 4th place was .02 seconds. This indicates that lane position and the speed of sound could have an effect on the outcome of an event.
I suggest electrical stimuli - 240v should suffice
So. Rather than have the pistol in line with the row at one side, how about having it in the middle halving the dis-advantage at the extreme(s). Even better, have the pistol central but step back 10 - 20 foot or so and that reduces the differential even further. Seems more practical and a lot more inexpensive than a super dooper electronic system.
You Americans still don't get this metric stuff do you.
Of course we do. There are 1.6 kilometres to the gallon, and 3 litres to the American non-statutory country mile (the liquid mile, that is; a dry mile is 3 9/8 bushels longer, except in Kansas where it's *another* 7 degrees higher and isn't allowed to be measured at all on a Sunday).
Back in my track days, we were taught to go by the smoke of the pistol, not the bang.
For that to even be remotely effective, your track team must have smelled really really fast.
The Admin and the Engineer
30ms seems to be the most common figure cited. 50ms was an aggregate of other studies I found (from a simple google search) which were typically in the 40-60ms range.
http://biae.clemson.edu/bpc/bp/Lab/110/reaction.htm
How can I believe you when you tell me what I don't want to hear?
You Americans still don't get this metric stuff do you.
His problem was not in misunderstanding the metric system, his problem was in failing to do simple algebra.
Apparently wizard is not a legitimate career path, so I chose programmer instead.
I find it funny that the US gets criticized for not being metric, when the UK isn't either. Officially sure, but they all talk in pounds and stone and ounces.
If you ignore ACs because they are anonymous - you're an idiot.
Great, now that the "real" athletes are also complaining about ping times, can we make FPS olympic?
... 0.03 sec is not very much ...
0.03 sec is enormous in the context of the Olympics. The difference between Gold and Silver medals is sometimes 0.01 sec.
The UK system is easy to remember.
Beer is in Pints. Except when it is Foreign. Then it should be in pints, but them damn foreigners don't know what they are doing.
Milk is in pints.
All other liquids are in metric.
People are measured in imperial. Except newborns who are metric.
All food, except steaks are metric.
Distances when using a road are imperial. All other times metric.
Wow, I should not post when knackered.
I find it funny that the US gets criticized for not being metric, when the UK isn't either. Officially sure, but they all talk in pounds and stone and ounces.
All actual work is done in metric.
The imperial holdovers are in a few bits of daily life: road speeds and distances (but the roads and cars are built using metric measurements), human height and weight (but doctors always use metric), beer volume in pubs.
(Other daily life things are metric: temperature, buying and cooking food, building construction etc.)
It's stupid, and I wish we'd just finish the transition, but it's nowhere near as annoying as the US.
I suggest electrical stimuli - 240v should suffice
Better be DC or high freq AC (like a tesla coil) because an AC waveform has a longer wavelength than the kind of measurements they're already complaining about.
For example a anal probe activated at a voltage zero crossing would take around 5 ms to reach peak voltage at 50 hz, but the americans would whine because they're used to 60Hz which only takes 4ms to reach peak voltage. And the other competitors would whine because the 220 volt probe would reach the 110 volt level that the americans train with in only about 2 ms, whereas they're used to waiting until a voltage maximum at 5ms to react. As you can see even low frequency RF aka "power electronics" is all rather complicated. This is before power factor correction, where athletes with inductive or capacitive digestive systems would lead/lag and the nervous system is inherently current mode logic anyway (or is it? Some MD or bio guy needs to weigh in) (hmm, digestive system is shaped inductively all curly and stuff, but digestion is all about capacity aka a capacitive reactance... anyone other than space alien abductors got a smith chart plot of a human digestive system based on probe data?)
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
For the 200m and 400m, they have staggered starts along the curve so the distance between sprinters is much greater.
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There is inferior bacteria on the interior of your posterior.