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How much does a ball weigh in 30 degrees as opposed to 8o ?

How "tight" is a 30 degree ball as opposed to the same inflation psi in 80 ?

If I'm anywhere near correct ... filling a ball to 10 lbs (I have no idea ... just using a number) in 30 deg and setting it aside for an 80 deg day would necessarily "tighten" it due to the expansion .. and vice/versa

I think this is all a bunch of Ferguson

How much does a ball weigh in 30 degrees as opposed to 8o ? How "tight" is a 30 degree ball as opposed to the same inflation psi in 80 ? I wonder, do they ever just use Nitrogen instead of Air? Tires with Nitrogen last longer and leak less. At 80 psig and 30 F, the density of air is 0.5236 lb/ft3 At 80 psig and 80 F, the density of air is 0.4870 lb/ft3. Volume of a football is 0.149628 ft3 (4,237 cm3)and the weight of the ball without air is 0.9061 lbs. So the ball filled with 30 F air would weigh 0.9844 lbs. and the ball filled with 80 F air would weigh 0.9790 lbs for a difference of 0.0055 lbs (0.088 oz or 2.5 grams) ==================================== These cats say the volume of a football is http://www.csus.edu/indiv/o/oldenburgj/ENGR1A/NFLFootballWtCalc.pdf NFL Football Weight Calculation Figure 1. Football axes: a is the polar axis, b is the equatorial axis Physical Measurements (at 20 °C) Weight of Football without air – WF = 14.5 Oz = 411 g a = 14.0 cm, b = 8.50 cm Guage Pressure -- PG = 13 psi (Pressure above Atmospheric) Atmospheric Pressure – PA = 14.504 psi Pressure of Football – PF = PA + PG = 27.504 psi Molecular Weight of Air – mWAir = 28.96 g/mol Molecular Weight of He – mWHe = 4.00 g/mol Molecular Volume – mV = 24506 cm3/mol Volume of Football – VF = (4/3)πab2 = 4237 cm3 Calculation of Weight Weight of Air in Football = € WAir = mWAir PFVF (mV)PA  = 9.67 g Wight of He in Football = € WHe = mWHe PFVF (mV)PA  = 1.34 g Weight of Football with Air = WF(Air) = WF + WAir = 421 g = 0.421 kg Weight of Football with He = WF(He) = WF + WAir = 412 g = 0.412 kg Conclusion: The He-filled football is about 2% lighter than the Air-filled football.