Facts, Not Fiction

 
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    Great Southwest Classic 2019 [with WYR]
    #1
    11.02/22.88 (with a -1.6) Brianna Williams
    51.57 Jan'Taijah Ford

    10.15/25-0.5 Matthew Boling

    39.05 all-star 4x100 team

    more to come
    Last edited by gh; 06-18-2019 at 05:33 PM.
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    #2
    Justin Robinson... 44.84!!!

    #2 A-T HS
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    #3
    Kennedy Lightner 20.48 (-0.4)
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    #4
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    Do all of the sprint/LJ-TJ marks carry an (A)?
    Last edited by 26mi235; 06-09-2019 at 07:23 PM. Reason: and => an
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    #5
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    Quote Originally Posted by 26mi235 View Post
    Do all of the sprint/LJ-TJ marks carry and (A)?
    They should.
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    #6
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    The 100m. His closest competition appears to pull a hamstring halfway.

    https://www.youtube.com/watch?v=q7cg6_g-7rk
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    #7
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    Quote Originally Posted by gm View Post
    51.57 Jan'Taijah Ford
    JaníTaijah Ford's (FlHS) 51.57 is the HS SL (if you allow post-grad meets) and one guess where she's going . . . the rich get richer . . . USC (and not the one in Columbia).
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    #8
    Quote Originally Posted by 26mi235 View Post
    Do all of the sprint/LJ-TJ marks carry an (A)?
    Yeah for freaking Awesome!

    Yes all marks done at 5300 feet would carry an "A" for Altitude. The break-over seems to be at 600 meters as anything past that would need aerobic support where any event under that distance could be done anaerobically.

    But heat and relative humidity along with barometric pressure also can effect the outcome of sprinting events just check out the NCAA thread, the high humidity and heat helps with friction which can also hinder sprinting.

    Maybe all the sprint, hurdle and horizontal jumps at the NCAA Championships should have an "S" for slippery by those marks!

    P.S.

    For all those super serious readers out there the last sentence was a joke.
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    #9
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    Relative humidity has nothing to do with it, it is the dew point, which essentially tells you how much moister is in air. When the temperature is 45 degrees and the relative humidity is 100% And it is those molecules of H2O, lighter than O2 and N2 that lowers the mass of the air.

    Take 50 degrees, 100%RH at normal pressure in air and there 9.40 grams of H2O and 12269 ppm in a cubic meter of air.
    95 degrees, and dew point of 78, RH 58.2%; 23.04 grams of moisture and 33416 ppm.

    So there are more than three times as many lighter water molecules in a cubic meter (3.34% verses 1.22%) and that makes the air less dense. It takes the air mass from 28.70 down to 28.47, a 1% reduction in air mass. (If you compare 95/78 with 78/65, 64%RH, and the mass decrease with the higher dew point is 0.56%)

    This is a pretty extreme example that illustrates both that the RH is not the right measure, dew point is. It also shows that it makes very little difference and people ought to stop stressing it so much. But it is extremely rare to get dew points above 85 (record is ~low 90s I think)

    If you cannot understand this set of calculations and the implications then you should not be talking about the effect of humid air on track times. RH has commented the the density effects are pretty small. By the way dew points in the 70s are pretty common in the US, even up here sometimes.

    http://www.michell.com/us/calculator/
    Last edited by 26mi235; 06-10-2019 at 06:07 AM. Reason: adding link to the calculator
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    #10
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    Quote Originally Posted by 26mi235 View Post
    Take 50 degrees, 100%RH at normal pressure in air and there 9.40 grams of H2O and 12269 ppm in a cubic meter of air.
    95 degrees, and dew point of 78, RH 58.2%; 23.04 grams of moisture and 33416 ppm.
    So there are more than three times as many lighter water molecules in a cubic meter (3.34% verses 1.22%) and that makes the air less dense. It takes the air mass from 28.70 down to 28.47, a 1% reduction in air mass. (If you compare 95/78 with 78/65, 64%RH, and the mass decrease with the higher dew point is 0.56%)
    I'm sorry, this is Summer Vacation - no math allowed!
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