Month: January 2015

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Patriots “Inflate-gate”

I wish to thank the NFL and the New England Patriots for giving all of us STEM teachers an opportunity to help teach some science.  During the AFC championship game, the New England Patriots were found to have been using balls during the game that were under inflated.  I’m not going into the football or controversy behind this, the press is all over this.  Go and run an internet search for these kind of details.

I’m interested in the Physics here and the opportunity to teach students some relevant classroom curriculum. Much of the media and fan rantings is that when the ball is inflated in a warm area and then brought out to the cold field it will decrease in pressure.  OK this makes sense.  Let’s check out the Math(eek, not Math!!)

According to the Ideal Gas Law.  Gas (like air) has a relationship spelled out as PV=nRT.
P is the pressure of the gas
V is the volume of the gas
n is the number moles of gas there are (how much air)
R is a constant for used for the gas
T is the temperature of the gas.

The balls weighed before and after the game have things that will not change such as Volume of the ball, number of moles of air in the ball, and the constant of the air.  So the only variables are the pressure and temperature.

First, this law is used with SI units.  So we need to do some converting.  According to NFL rules all balls to be used in the game are to be inflated to between 12.5 and 13.5 PSI of pressure.  Using Google to convert the units that’s 86,184.4662 to 93079.2235 Pascals of pressure in each ball at game start.  For argument’s sake, let’s say the room temperature the ball’s were checked pre-game was at 72 degrees Fahrenheit.  Again, using the wizardry of the internet, this converts to 295.372 degrees Kelvin.  Game start temperature was reported to be about 51 degrees Fahrenheit.  But, the ball issue didn’t become apparent until the third quarter, it had gotten colder out.  Let’s say it got to about 40 degrees Fahrenheit (the temperature it was on my way home after the game.)  This converts to 277.594 Kelvin.  Much of the conversation I have found on the internet has failed to convert the numbers to SI units making some pretty odd results.

Going back to the formula, we will be looking at the on field pressure at 40 degrees Fahrenheit.  The balls would drop to between 87997.2 and 87476.9 Pascals of pressure or 11.7 to 12.7 PSI.

So, yes, the cold weather would make a difference in the pressure of the balls used in the AFC game.  But, the NFL reported the balls used by the Patriots were under inflated by over 2 pounds per square inch.  The cold could not have accounted for this much pressure drop.  I’m not claiming the Patriots knowingly cheated, there are too many people involved in the handling of those balls.  But, I do claim that the under inflation was not due to weather alone.

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Difficulty about coaching middle level football

One of the largest difficulties I have faced in designing a program for Middle Level football is the lack of resources about such programs.   There has been a lot of material written for the high school level and college level programs and plenty for youth coaching.  But, Middle school athletes are capable of more than what younger children can accomplish, yet cannot run high school schemes yet.  There are of course exceptions, like if you coach talented select teams that cut non-performing athletes.  But, here at Mahar, anyone who steps on the practice field plays.  Many years we struggle with enough numbers to run effective practices.

So, my solution at first was to use a watered down version of our high school program.  I figured this would get our athletes in tune to the philosophies and techniques they will see later.  This would make transitions easy and create one solid 7-12 seamless program.  This did not work as I would hope.  Again, as stated in the last paragraph, our athletes could not perform the same schemes as a varsity program.  They did not posses the football knowledge or physical ability to perform.  Watching 11-13 year olds attempt zone blocking is quite the site.  And, we saw very different opponent schemes than our varsity counter parts.  Our needs on offense and defense did not align with the varsity program’s.

So, I went backwards instead.  I started looking into youth programs which showed success at the early years.  I ran into Dave Cisar’s book, “Winning Youth Football.”  this is an excellent resource which outlined a philosophy which was perfect for my team.  We started implementing the defense after our first week one loss of the season and then installed a variation of the offense starting the second week.  This book outlines a successful program and addresses how to implement the system for older teams.  Our coaching staff put together our first winning season, 5-3, using parts of this system.  We will integrate more of it this coming fall.  I can’t wait to see the results.

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self learning

The most important job I have as an educator, in my opinion, is to leave my students with the ability to teach themselves.  After all, once they leave our schools they will have a lifetime of learning to acquire.  Most of which without a formal teacher.  I’ve been introducing lessons which make the students use manipulatives, software, and internet resources such as Kahn academy and web quests to learn math skills.  All I’ve been getting from my students is, “I don’t get it”, “how do I do this”, or the usual blank stare of daydreaming.  I know they can give more than i’m seeing, but laziness and unwillingness to think for themselves takes presedence.  Research may state open ended and student centered lessons create better thinking and greater learning outcomes along with higher levels of engagement.  Yet, many of my students will just sit there and do next to nothing unless I hold their hands throughout the exercise.  It has been an uphill battle I have made very little gains with, but I refuse to give in.  Any thoughts on turning this classroom culture around would be greatly appreciated.  Grades are not a motivating factor.  Most of these students have come accustomed to failing and D’s are welcome surprises.