(Science weighs in on 'inflategate') Football Physics: Why Deflated Balls Are Easier to Catch

[icymist]

After an inspection revealed that some of the footballs used during Sunday's NFL playoff game were slightly deflated, many people are asking whether the balls gave the New England Patriots an unfair advantage over the Indianapolis Colts.

Last Sunday (Jan. 18), the Patriots landed a spot at the Super Bowl after beating the Colts 45 to 7. But an NFL inspection at halftime found that 11 of the 12 footballs the Patriots brought to be used in the game were underinflated, according to ESPN.

Just how advantageous is it to play with a deflated football? A ball that is less inflated is easier to deform and grip, said Miguel Morales, an associate professor of physics at the University of Washington.
http://www.livescience.com/49539-deflated-football-pressure.html

[caraher]

1. I thought it was lazy of them not to say how much the cold would change pressure

It's a trivial calculation - if you have the pressure at a known temperature, neglecting any slight volume changes in the ball the pressure will just be proportional to absolute temperature. The only trick is to remember to calculate Celcius to Kelvin or Fahrenheit to Rankine. It's a high school chemistry problem.

The numbers show that the observed pressures were too low to be caused by temperature change alone. (At most the change would be less than 1 PSI; the Pats' balls were low by 2 PSI). Plus the Colts' balls, subject to the same temperature changes, were not underinflated.

[sailfla]

2. Thank you very much for the research. That has been on my mind.