NDL Forum

nick wrote:

dakshdar wrote:

nick wrote:are you taking into account that the balls were more than likely pumped in a locker room, and brought outside to a colder temp?

Ummmm...

I assumed the balls were filled/checked indoors and then later checked outdoors (which is where the discrepancy would have been discovered, presumably). That was the entire point of the calculation determining the change in pressure due to the change in temperature.

Guess I lost you somewhere.

well some scientist from Boston had this to say

“One complication with the pressure units that we usually use, in this case PSI (Pressure per Square Inch) is that we are measuring the pressure above the atmospheric pressure,” Schmaltz said. “Air at a fixed volume- and I assume the size of a football stays pretty much the same whether it has a PSI of 13 or 11- if the size stays the same, and you change the temperature of the air, the pressure inside the football changes as well.”

The key question, as outlined by Schmaltz, is where the balls were tested prior to the game.If the balls were tested indoors, where the temperature was likely above the 50 degree temperature outdoors Sunday, then the pressure inside the ball would drop once the ball is moved outdoors and begins to cool off.

“If they had inflated the balls inside the building and put it to the minimum amount, and then brought it outside to temperatures that were about 30 degrees lower, that would drop the PSI by between 1 and 2,” Schmaltz explained.

According to Schmaltz, once the temperature of the air inside the ball drops to the temperature of the air outside the ball, the PSI would be changed. Schmaltz estimated that it would take no more than 30 minutes for the temperature of the air inside the ball to acclimate to the temperature of the air outside.

“After the game, if you take the ball inside to a commissioner’s office or another warm place, the air in the ball would warm up again and the PSI would go back up,” said Schmaltz.



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so basically what i said til Dak came in with some math

dakshdar wrote:

nick wrote:

dakshdar wrote:

nick wrote:are you taking into account that the balls were more than likely pumped in a locker room, and brought outside to a colder temp?

Ummmm...

I assumed the balls were filled/checked indoors and then later checked outdoors (which is where the discrepancy would have been discovered, presumably). That was the entire point of the calculation determining the change in pressure due to the change in temperature.

Guess I lost you somewhere.

well some scientist from Boston had this to say

“One complication with the pressure units that we usually use, in this case PSI (Pressure per Square Inch) is that we are measuring the pressure above the atmospheric pressure,” Schmaltz said. “Air at a fixed volume- and I assume the size of a football stays pretty much the same whether it has a PSI of 13 or 11- if the size stays the same, and you change the temperature of the air, the pressure inside the football changes as well.”

The key question, as outlined by Schmaltz, is where the balls were tested prior to the game.If the balls were tested indoors, where the temperature was likely above the 50 degree temperature outdoors Sunday, then the pressure inside the ball would drop once the ball is moved outdoors and begins to cool off.

“If they had inflated the balls inside the building and put it to the minimum amount, and then brought it outside to temperatures that were about 30 degrees lower, that would drop the PSI by between 1 and 2,” Schmaltz explained.

According to Schmaltz, once the temperature of the air inside the ball drops to the temperature of the air outside the ball, the PSI would be changed. Schmaltz estimated that it would take no more than 30 minutes for the temperature of the air inside the ball to acclimate to the temperature of the air outside.

“After the game, if you take the ball inside to a commissioner’s office or another warm place, the air in the ball would warm up again and the PSI would go back up,” said Schmaltz.



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so basically what i said til Dak came in with some math

Right. The equation is a simpler version of the ideal gas law, pv=nrt. In our case we're only interested in p (pressure) and t (temperature) as the other values are not changing.

P1/T1 = P2/T2 is the relationship we examine. We know the two pressures, it's 10.5 PSI (or 25.2 PSI absolute when you include the atmospheric pressure) at the cold temp of 283.15 K (50 F) and the (at minimum) 12.5 PSI (or 27.2 PSI absolute) at the presumably warm temp room the balls were filled in.

You have to use absolute pressure and absolute temperature (which is why it was done in kelvin) or the answer doesn't come out right.

The more interesting calcs pop up if they happened to fill the balls to 13 or 13.5 PSI initially. The temp of the room where they were filled would have to jump significantly to about 317 K or ~111 F. Maybe they fill them in a sauna?

dakshdar wrote:One simple fix for the NFL is that all balls should be tested outside 2 hours before kick-off (if they're serious about this). Unless you get a crazy weather change, it helps eliminate one main variable.

shel311 wrote:

dakshdar wrote:One simple fix for the NFL is that all balls should be tested outside 2 hours before kick-off (if they're serious about this). Unless you get a crazy weather change, it helps eliminate one main variable.

Or have a NFL official type person be in charge of the footballs, not these Seeit types!!!

But seriously, don't have guys employed by teams in charge, have an NFL guy. Problem solved.

But that won't happen, the NFL is too worried about Lynch wearing gold cleats!!!!

shel311 wrote:

dakshdar wrote:One simple fix for the NFL is that all balls should be tested outside 2 hours before kick-off (if they're serious about this). Unless you get a crazy weather change, it helps eliminate one main variable.

Or have a NFL official type person be in charge of the footballs, not these Seeit types!!!

But seriously, don't have guys employed by teams in charge, have an NFL guy. Problem solved.

But that won't happen, the NFL is too worried about Lynch wearing gold cleats!!!!

cougnix wrote:If he played with them, the first play he was a part of he would have gotten a flag, the second he would have been ejected

nick wrote:While its stupid, can you go to work with gold cleats on? or a random tshirt. probably not.

shel311 wrote:

cougnix wrote:If he played with them, the first play he was a part of he would have gotten a flag, the second he would have been ejected

I'm wondering if that's one of those rules the NFL made up on the fly.

shel311 wrote:

cougnix wrote:If he played with them, the first play he was a part of he would have gotten a flag, the second he would have been ejected

I'm wondering if that's one of those rules the NFL made up on the fly.

cougnix wrote:

shel311 wrote:

dakshdar wrote:One simple fix for the NFL is that all balls should be tested outside 2 hours before kick-off (if they're serious about this). Unless you get a crazy weather change, it helps eliminate one main variable.

Or have a NFL official type person be in charge of the footballs, not these Seeit types!!!

But seriously, don't have guys employed by teams in charge, have an NFL guy. Problem solved.

But that won't happen, the NFL is too worried about Lynch wearing gold cleats!!!!

How dumb was that? If he played with them, the first play he was a part of he would have gotten a flag, the second he would have been ejected. And on top of that, he is now getting fined every time he grabs his crotch.

Seeitsaveit13 wrote:

shel311 wrote:

cougnix wrote:If he played with them, the first play he was a part of he would have gotten a flag, the second he would have been ejected

I'm wondering if that's one of those rules the NFL made up on the fly.

Nah it's there. They technically can flag people for no knee/thigh pads and then eject them along te same timeline. It's all based on number of offenses and previous fines.

I used to cringe when the uniform inspector would give us the list of guys ready to be fined and when we'd warn them they'd go "oh I'll just take the fine". The smallest one was 5k... Fuck it. Wear the right shoes and give me the 5k you don't want. Fuck sake!

cougnix wrote: then complain they have a knee, thigh or hip soreness...lol

shel311 wrote:

nick wrote:While its stupid, can you go to work with gold cleats on? or a random tshirt. probably not.

There were Packers players in that same game with bright yellow cleats on, it's really not THAT much different.

But I do wanna wear my Auburn hat every other casual Friday like Pino suggested!!!

nick wrote: If Lynch doesnt like them saying he cant wear gold shoes, he can give all the millions back he got from playing a sport, and go work a 9-5. Based on how retarded he sounds, I can only imagine what job he would get if he wasnt blessed with athletic ability.

OracleHCR wrote:

nick wrote: If Lynch doesnt like them saying he cant wear gold shoes, he can give all the millions back he got from playing a sport, and go work a 9-5. Based on how retarded he sounds, I can only imagine what job he would get if he wasnt blessed with athletic ability.

He graduated from Stanford. He is a lot smarter than he sounds in his interviews.

cougnix wrote:

Seeitsaveit13 wrote:

shel311 wrote:

cougnix wrote:If he played with them, the first play he was a part of he would have gotten a flag, the second he would have been ejected

I'm wondering if that's one of those rules the NFL made up on the fly.

Nah it's there. They technically can flag people for no knee/thigh pads and then eject them along te same timeline. It's all based on number of offenses and previous fines.

I used to cringe when the uniform inspector would give us the list of guys ready to be fined and when we'd warn them they'd go "oh I'll just take the fine". The smallest one was 5k... Fuck it. Wear the right shoes and give me the 5k you don't want. Fuck sake!

I was wondering about that pad thing. I don't understand why they don't wear the pads, then complain they have a knee, thigh or hip soreness...lol