Deflation-gate

I suspect that the physics issues are overblown. In any event, an atmospheric (barometric) excursion of more than 1/4 psi or so would be extremely unlikely. So I think only the temperature explanations are worth considering.ABE: One atmosphere is about 14.7 psi.
END ABE When would this letting air out have legally happened? Presumably, absent some leakage, the balls ought to contain the same amount of air when the NFL got around to testing them as they did when they were used in the game. Whatever beefy handling (and deflating) occurred happened presumably happened before the balls were checked by NFL officials.And unless the NFL re-tested the balls in cold conditions, I don't see how any of the physics stuff comes into play. If it is true that the Colts balls were up to par, and that the re-testing was conducted at room temperature, where is the opportunity for Charles or Boyles, or whoever's gas law to take effect? I've seen the pot shots taken at the NFL about their knowledge of physics. But so far I don't see any evidence that those shots are warranted. Edited by NoNukes, : No reason given.Edited by NoNukes, : No reason given.

I meant to comment on this one earlier. The Colt linebacker who intercepted a Brady pass in the first half says he did not detect anything wrong with the ball. Apparently someone he gave the ball to on the sidelines did notice.And, the ball almost certainly was under inflated. I think the amount of deflation in question would be detectable. I have not much experience with footballs, but I can tell you that when I played a lot of basketball, I could easily detect small amounts (much less than 1 pound) of under inflation simply by handling the ball for a few moments.

Squeezing it between my hands, and attempting to 'palm' a basketball with each of my left and right hand would be enough to detect under inflation and over inflation of a standard size and weight men's basketball. Dribbling the ball would be very revealing of course, but not necessary.And yes you can bounce a football in a way that would help reveal under pressure. You cannot dribble a football down the hard wood, but a single bounce on a known surface would probably be revealing.I would be complete surprised if a professional football player who handles the ball frequently was not even better at detecting inflation with a football that I am with a basketball. Tom Brady is said to have relatively small hands, and has said that he has a preference for having the football inflated to the low end of the range, while Aaron Rodgers, who has larger hands, has expressed a preference for footballs inflated to the upper end of the range. I suspect that each of these guys gets what he wants on game day. He also does not play quarterback. Please describe those trials. Possibly. But perhaps that person had some reason to suspect under-inflation.

To be frank, I think the whole thing is a bit silly. I've seen an article in the press that suggests that one team has their balls 'customized' for their quarterback so that they get the desired 'feel' with normal inflation. Apparently that is completely legal to do.That said, why are Aikman and Brunnel not credible to you? If there was meddling, who would be foolish enough not to have that meddling cater to Brady's preference?Some of the stories about the testing would seem to rule out changes in temperature being an issue, but who knows if those stories are accurate?

The temperature of the air in the ball is what determines the pressure/volume and not the skin temperature of the ball, which might be something different at least during filling. Your explanation should be about how hot air got put into the ball. Seriously, Percy? You sound like someone who wants this pressure idea to work. So what happened to the 12 balls that were not under inflated?

A football is made of insulating material of unknown heat capacity. How long after you tucked the ball under your jacket would it take to see a significant pressure change. If you kept the ball against your skin for five minutes and then put it back on the table, how high would the pressure get?

The volume of an inflated ball is not constant, nor does it increase proportional to pressure. Any analysis that does not take that into account and uses some naive application of the ideal gas law is going to be wrong. And by wrong I mean that they will over estimate the change in pressure for a given temperature rise.I have seen a few calculations by amateurs that are surely incorrect, and also some statements from experts that don't reveal their assumptions. Not sure how anyone can figure out which experts to trust.Edited by NoNukes, : No reason given.Edited by Admin, : Fix italic close code.

Not really, Percy. It just means that I have handled basketballs and checked their pressures reasonably often. You seem to be mocking me, Percy. Well that's your right. But I've seen people 'dribble' a football on a table for a few bounces. I cannot do it myself, but I don't have particularly good 'handles'. Whether or not you could detect the pressure differences in question with such bouncing is speculation on my part.A number of players have expressed preferences which suggests (but of course does not prove) that differences in pressure are meaningful. I suspect instead that you haven't handled very many official basketballs. There's nothing particularly special about it. Perhaps Bellichick is unable to tell the difference. Perhaps lots of people cannot. But given my own experience, I suspect that only more detail, and not simple denials from Bellichick are going to be required. At least for me anyway. Edited by NoNukes, : No reason given.

Thanks 12 chicken.

Again, the temperature of the skin of the football is largely irrelevant.Inflating an already inflated football takes a few seconds. The pressure is going to be dominated by the temperature of the air put into the ball from the room. Your scenario does not work.There may or may not be enough evidence to make a call. The problem is the uncertainties surrounding the information that we do have. I have no idea how you are making the call that there is insufficient evidence.

I doubt that Aikman know how the Patriots do things.But I believe that Aikman might well knows something about the relationship between the team's quarterback, and whoever it is that is responsible for inflating the balls to a pressure between 12.5 and 13.5 pounds. I've explained that at least twice Percy. Regardless of the temperature on the field, we can compare the pressure in the balls when they reach equilibrium at room temperature. Or we can compare them at the temperatures on the field when the referee's checked them.

Because some amount of 'messin' with the ball is allowed. I don't see any problem with the balls being scuffed up a bit. I used to hate playing with brand new basketballs because they are general too slick. It should be enough for the referee to check the pressure, but at some point control is turned over to the teams.

That's fine Percy. You don't believe that they removed the balls from the field. I am reserving judgment until I hear what tests were conducted.

It does not matter what the intent was. The skin of the ball does not determine the pressure of the air inside. And both the skin and the bladder are made of materials that do not conduct heat very well. Viable absent some actual calculations involving the temps and pressures actually involved, yes.To be clear, I am not arguing about whether temperature affects the pressure in the ball. I'm suggesting that some of the scenarios postulated here that have to do with inflating the footballs when they were cold are nonsense. Edited by NoNukes, : No reason given.

That strikes me as a bit non-intuitively high. You used absolute temperatures (Rankine scale) of course. Assuming room temp of 70 degrees or about 530 on the Rankine scale we'd expect the pressure to exhibit approximately the same percentage change as the temperature. So to get a 2 parts in 28 psia decrease. Sounds like something on the order of a 30-40 degree change in temperature. I recommend a math recheck. Not much chance of that being an issue. CO2 is the most problematic, but that ought to be no more than 1% of the air. Air is pretty close to an ideal gas over the puny temperature and pressure ranges involved here.My problem with the data is that a temperature change that drops a ball outside of the spec by 2 pounds ought to even balls inflated near the top of the range out of spec. Yet no problem is observed with any Colt ball, and with some of the Patriots footballs. The explanation cannot simply be the temperature excursion.