The Physics of Natural Football Deflation

Discussion in 'Fred's House of Pancakes' started by SageBrush, Jan 21, 2015.

  1. SageBrush

    SageBrush Senior Member

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    Exactly right.

    This table
    http://gapyx.com/cmt/2008/01/dsm_absolute_humidity_relative_humidity.jpg

    shows that IF (they didn't) the football had been inflated with 100% relative humidity air at 23C (73F), every 1000 liters of air pumped in would have contained about 2 grams of water. 1000 liters of dry air weighs 1.29 Kg (2.84 pounds.)

    So even if ALL the water vapor condensed (not even close,) the pressure in the ball would have dropped by 2/1290. That is about 0.02 psi, meaning well within the margin of error of a simple air pressure gauge.
     
    #141 SageBrush, Feb 5, 2015
    Last edited: Feb 5, 2015
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  2. Yakoma

    Yakoma Active Member

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    If you watched the Super Bowl (or practically any other college or NFL game this year), you will hear the color guy say something the effect of: "Jones really made a sly move there and gave the receiver a push before the ball arrived...that's the mark of a true veteran cornerback" or "Daniels went with a hard count and drew the defense offsides for the 1st down...that clearly should have been a penalty" or "Did you see Markum grab that facemask...that was clearly deliberate but he got away with it...if he hadn't done that would have been a pick six."

    So, ask yourself, really, what are we arguing about?

    - That football teams cheat?
    - Or, are we trying to draw fine lines about what is acceptable cheating what is unacceptable cheating?
    - Or, are we condemning the Pats for being stupid enough to get caught?
    - Or, are we really expecting them, now caught, to be more honorable than the next team and actually admit to cheating?
    - Or, are some of us hating on the Pats because they're on top and our team is not?

    Come on.

    What I think we're doing is just killing time waiting for football season to start again.

    And, by the way, don't you think the NFL owners and players and agents, ESPN, Fox and all the other networks and all the sponsors secretly LOVED the fact that the DeflateGate controversy kept football front and center in the spotlight worldwide for two straight weeks leading up to the Super Bowl - which garnered the largest audience ever to watch a TV event?
     
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  3. SageBrush

    SageBrush Senior Member

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    ^^ The only thing I want to add to your excellent post is that unfair cheating (as in, both sides do not have equal opportunity) only matters if it changes the result.

    Since I do not gamble and do not care about handicaps, it is easy for me to say that even if I thought that NE cheated with their football inflation (I don't), I say it does not matter.
     
  4. bisco

    bisco cookie crumbler

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    good thing spring training is starting soon, no cheaters there.:cool:
     
  5. wjtracy

    wjtracy Senior Member

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    Race car drivers do have to worry about water because at 100 deg C it can bulge out tires when it vaporizes.
    But us mortals not so much.
     
  6. wjtracy

    wjtracy Senior Member

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    OK here's an orig deflategate calc, by me, so be careful, I am rusty on this:

    How many PSI does the football lose per second with a typical deflating needle (1-mm inside diameter)?

    The max flow rate will be the speed of sound thru the needle at 60F = 1120 ft/sec = 34138 cm/sec
    So we have 1mm hole = 0.00785 cm2 x 34138 cm/sec = 268 cm3/sec leak (at 27.7 psia) = 505 cm3/sec (standard temp and pressure)

    Football is about 4200 cm3 which means it holds 4200 x 27.7/14.7 = 7914 cm3 (standard temp and pressure)
    So each second we lose 505 ccs of 7914 ccs total = 27.7 x (505/7914) = 1.76 psia loss per second

    This is max. leak rate as I forget how to calculate if max leak rate is true as low as 13 psig (27.7 psia)

    EDIT: Choked or sonic max leak flow rate will be true, right down to about 27.7 psia, below that pressure the leak rate will slow a bit. So my calc above should be on the borderline of correctness, assuming no bugs in my math.
     
    #146 wjtracy, Feb 6, 2015
    Last edited: Feb 7, 2015
  7. Chuck.

    Chuck. Former Honda Enzyte Driver

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    At some of the sports forums, this topic is the type that would definitely go to Fred's House of Politics - because it's politics, religion, or football. :D

    To be honest, facts don't matter, but how you feel about the New England Patriots in those discussions:
    • One side considers the Patriots as serial cheaters since 2001, even to the point it's the only way they have won SBs....they are guilty because they have done so in the past.
    • The other side is in a bunker mentality....rivals are making stuff up and cheat themselves.
    I'm waiting for an objective or semi-objective source to find if the Patriots cheated a lot more/better than the rest of the league....I lean that there's plenty of cheating everywhere. While I definitely object to videotaping opponents and deflating footballs, neither do I think it gave the Patriots a significant advantage and definitely not worth the bad PR.
     
  8. bisco

    bisco cookie crumbler

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    gonna be tough to find anyone objective, even the nfl hierarchy. and even if they were, whichever side loses will be howling about the fix being in.

    it would have been simpler if they handled these things like any other rule breaking: your balls were measured under pressure, this is the penalty, done. but because it is political, because no one knows if the refs actually checked the balls, because they don't have a precedent for checking the pressure at game time and someone had to drop a dime, it becomes a 3 ring circus.
     
  9. SageBrush

    SageBrush Senior Member

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    huh.
    OK, I'm almost done laughing. In your world, is physics "objective?"
     
  10. bisco

    bisco cookie crumbler

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    jerry rice just admitted to putting 'stickem' on his receiving gloves illegally, back in the day. he still called out the pats though.
     
  11. SageBrush

    SageBrush Senior Member

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    When Jerry Rice has proof of something illegal, I'll all ears.

    In the meantime, has he said how he wants his cheating to be handled by the NFL ?
     
  12. bisco

    bisco cookie crumbler

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    yep, everyone was doing it.:cool:
     
  13. SageBrush

    SageBrush Senior Member

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    Rice is the smoking gun for HIS cheating; his finger pointing of others is unproven.

    I'm a fan of Rice, but logic is not his strong suit.
     
  14. bisco

    bisco cookie crumbler

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    me too, but i think he really likes being thought of as the best ever. gotta give him creed for coming clean. he's like brian williams, people like him too much to be disappointed.
     
  15. SageBrush

    SageBrush Senior Member

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    He has a funny way of showing it. Irony is having a good day today.

    I appreciate Rice for much the same reason that I appreciate Fitzgerald: their dedication to their craft is amazing, and they are both almost superhuman athletes. Whether the ball stayed in the glove is less interesting.

    To me it is is like watching an outfielder in Baseball run across the field run with his back to the ball to exactly where the ball hits his glove.
     
  16. bisco

    bisco cookie crumbler

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    latest rumors; d'quell handed the ball to someone in the colts organization, who deflated it and called the ref's.
     
  17. wjtracy

    wjtracy Senior Member

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    At RadioShack you can buy little electronic pressure sensors (LittleBits), I am wondering if we can get one in a football and on TV we can see real time pressure chart. Cool when the punter kicks I bet!
     
  18. fuzzy1

    fuzzy1 Senior Member

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    ... if you can find one, still open, and with decent stock.

    Yesterday, after catching some business news, my curiosity lead me past the nearest store. Already shuttered, inventory moved elsewhere. Already removed from the online Store Locator. And not even on today's list of locations at risk, that appears to be for the next round of closings.
     
  19. Chuck.

    Chuck. Former Honda Enzyte Driver

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    Physics is objective, but not the people involved.

    As I said previously, I've looked at a couple of sports forums and the mentality is the facts must support my pre-conceived opinion because of my hate (or love) of the Patriots. In a month when the investigation is expected to be complete, expect the findings to be declared to be "rigged."
     
  20. SageBrush

    SageBrush Senior Member

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    I'll be damned -- a post I can agree with :)

    I was amused because you said an objective source. Is the source not a person, whom you have declared must have a pre-conceived opinion ? And just between you and me, where do you think that Physics textbook came from ?
     
    #160 SageBrush, Feb 7, 2015
    Last edited: Feb 7, 2015
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