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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."
They should just use a light instead of sound. Even at school we waved a flag to start because if we went by sound it would introduce an error into the timing.
Appropriate, for once...
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
Actually, it's one kilometer in 3 seconds, not 1/3.
Why not just lights? Works for F1.
Why not just move the starting gun to behind the athletes? The further back it is placed, the more equal the distance to each athlete. It doesn't get as much media attention though.
Highest bidder gets to hear the starting gun first
Why not skip that and just auction the medals
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.
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
As others already pointed out, you're not exactly a math genious.
Also, the article mentions they take a shitload of images and detemine the winner
this way (-> http://goo.gl/vKZFa - chest is, what counts).
Furthermore the speed of sound could easily explain a difference of let's say 0.02s (equivalent to ~ 6.5m)
and as you said yourself, sometimes that does make the difference.
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.
It's more like 10 meters. Which means the difference in time is 0.03s, which is (at the 100m sprint) significant, and can mean the difference between winning or losing, or between a world record or no record.
The guide dog pulls them along faster to make up for it.
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).
What confuses me is that the story says they're using speakers, meaning every player hears the sound at the same time. So where's the issue?
It seems that the speakers convey the sound of a guy with an actual gun further behind. But why aren't the players training themselves to react to the first sound, disregarding the real noise. More importantly, why the hell is there even a real gun out there if they've got the speakers? They couldn't have started using a prerecorded sound years ago?
It appears to me that the real story here is that these officials are so slavish to hopelessly outdated traditions that they'll continue sticking to them even long after it's become evident that it's detrimental. It reminds me of FIFA's long time refusal to accept replays or goal line technology.
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.
If the speed of sound would be a potential factor in determining who wins, it counts as a tie.
I have a feeling we'd see a lot of deaf people at least tying for first in the Olympics then.
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?
It isn't just the width of the lanes, of course. For some races, the sprinters are started with a considerable offset from one another along the track to account for inside-outside lane length differences.
... 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.
Give him a break. He's a Political Science graduate.
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.
You Americans still don't get this metric stuff do you.
Use the right tool for the job, in this case imperial. We're talking about feet in an olympic article about running and feet, so use feet to measure. Not millionths of the distance from Paris to the north pole or wavelengths of cesium or WTF arbitrary measurement a metre is. Use feet. Yes, it would be dumb to use human feet to measure an interplanetary space probe, but this is totally appropriate.
Sound travels at 5 secs/mile as anybody who's survived a thunderstorm and counted miles away by fives knows. In other words one second = 1000 feet or sound takes about "a thousandth" to go a foot. The article is babbling about measuring run times to ten thousandths of a second, and sounds takes one thousandth to go a foot, so it doesn't take a genius engineer or physicist to figure if you want tenths accuracy you need to position the speakers the same distance from the ears with tenth of a foot accuracy, or "about an inch". Which the olympic fools still aren't doing correctly, as near as I can tell.
Its all idiocy for show anyway. They have to start at the same instant because in ye olden days they didn't have computer measurements, so they determined the winner by who passed the line first. They should just run individually now and use chrono gates much like at a gun range. Yes yes, I know its motivational to run together and "compete" while running but these are adults not five year olds, so they can be expected to run "really fast all the time" even if not in a pack or herd. I'm sure the steroids will ensure a proper competitive attitude and outlook on life.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Exactly, Why not just time them from when they leave the gate, instead of trying to test their reaction time at hearing the pistol. This is how ski races are timed (ndividual events anyway). The EKG countdown is just to let you know when to go, but the timer doesn't start until you leave the gate, and the timer stops when you cross the finish line. I think running races would be much more interesting if we were only measuring the time they spend running, and didn't worry about how fast they reacted to sound. You could still have the gunshot and have them all race at the same time, but you wouldn't have to worry about false starts, and you wouldn't have to worry about who reacts fastest being the difference between first and fourth. I realize that the whole reaction time is part of the sport. But in events like the 100m dash where .1 seconds (or less) is the difference between first and second, it probably makes sense to eliminate any room for unfairness due to sound propagation.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
The fuel economy one is particularly problematic for UK vs US measurement.
http://en.wikipedia.org/wiki/Gallon#Comparison_of_historic_gallons
US uses the 1/128th of an oz - similar to other imperial measurements where it is powers of two for easy division.
(16 tablespoons in a cup, 4 cups in a quart, 4 quarts in a gallon).
The brits use 1/160th of an oz for some odd historical reason.
So, when I told someone my car was averaging 38mpg between fillups, he thought it was pretty bad, since for him that would be equiv to 31.6mpg in the US.
When I read a car report from Britain and I read that the car is getting 45mpg, I get excited at first, before I realise that's about what my car gets.
-- perl -e'print pack"H*","6e656d6f406d38792e6f7267"'
Uh.. wait... how wide is a Kansas Sunday again?
It depends on how many miles you have to go to get to a state line so that you can buy beer on said Sunday.
"[Each] day finds some six million high school students and two million college freshmen struggling with algebra. [...] Why do we subject American students to this ordeal? I’ve found myself moving toward the strong view that we shouldn’t."
"Making mathematics mandatory prevents us from discovering and developing young talent."
From the NYT Jul 28
http://www.nytimes.com/2012/07/29/opinion/sunday/is-algebra-necessary.html?&pagewanted=all
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.
If you think algebra was required for that math, then you already failed.
I haven't thought of anything clever to put here, but then again most of you haven't either.
Sure, that's easily accomplished technically. Except that's not the point of these particular races. Some races are against the clock, many of the cycling races for example. Shorter races, however, aren't against the clock; they are racer against racer. The clock is just there to compare across races and time. So, since the racers are racing against each other, not against the clock, there is all this fussing over starting at the same time.
0.44s - 0.135s = 0.305s. Speed of sound is 343m/s. Are we supposed to believe that the farthest starting position is about 343m/s * 0.305s = 104m further away from the pistol than the nearest? The guy's just slow.
I'm guessing you've never been to a track meet ...
In events like the 400m (one complete circuit of a standard track oval), people run in their lane the entire distance around the track. Because the outside lanes are longer than the inside lanes and the finish line is directly across the track, the starting positions are staggered to make the distance ran equal. Yes, that is a significant distance between the fellow in the outside lane (close to the starter pistol) and the fellow in the inside lane (far from the starter pistol), possibly quite close to the 100m you computed.
"Flame away, I wear asbestos underwear"
About 2 Libraries of Congress.
Precisely one week and 13 cubits... in other words, 2 parsecs, 14 hours and 23 cents.