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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
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?
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.
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?
... 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.
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 check and review a lot of engineering papers, I see about 3x the rate of order of magnitude type errors like this one with metric units compared to conventional units. Even from "native metric users".
Speaking of calling bullshit on something, the premise of this article is utter BS as well. The difference in time of arrival of the sound based on lane position is on the order of 30 msec, worst-case, not 300-ish.
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"'
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.
Just wanted to add...have you been to a drag strip?
Just another day in Paradise