To the editor:
As a current student of physics at Clarke University and fanatic college football fan, I would like to say that this article on the physics involved in a University of Nebraska football game spreads a positive light on how prevalent physics is to the world that we live in. The idea of collisions, ball trajectories, and spirals in football are often over looked when attending a football game or watching it television. I want to address and commend this article on how well it brought forth the presence of physics in football and discuss a few of the main points involving three-body collisions, momentum in a goal line plunge situation, and finally a balls spiraling in air towards a player to be caught.
Like Dr. Gay in this article, I attend many football games, rather as an athletic training undergraduate student instead of an experimental atomic physicist at Nebraska University. We do see football in a different light given his professional experience in the physics field or my lack-there-of experience as being a current student of physics trying to put all the concepts together and learning the material. But what I can say is that I agree with most of the ideas Dr. Gay brings forth in this article, and once a few ideas were stated in the article it made me think of how much physics actually does occur in a sixty minute game of football. Dr. Gay, in a sense helped me to bring concepts learned in my University physics class with those on the football field or more broadly, physics that happens outside of the classroom.
In this article, the first example involved three-body collisions, this more simply is when three objects hit each other at the same time. Each object has a force; a force can be as easy to understand as a push or a pull on an object. If one were to hit a ball, the force can be the swing of the bat meeting the ball which propels the ball away from the home plate. In Dr. Gay’s situation, two players and a ball meet and they all have a force being applied. From my understanding I would agree with this article when injury is explained and how the pads and helmets absorb the forces so that the players do not get hurt. I can directly connect this to my athletic training major that I am currently pursuing because I see this very scenario happen frequently. When I see this happen in real life, rarely does an injury occur due to the ball being flung off path and the players’ safety equipment receiving a majority of the force. For a person who has never seen a football collision (which would be hard to imagine), you can think of it in a different scenario. An example would be a shopping cart collision at a grocery store in which the carts absorb the forces.
What I found to be the most interesting part of the article was the discussion of a short goal-line plunge and the physics associated with that. Momentum is the main point discussed in a goal-line plunge. Momentum to me, and to simplify it for everyone else is the idea of the energy needed to move from point A to point B. If I want to stand up from a sitting position, I need to gain momentum to do so. Again, because I have such a fascination with football this scenario is interesting to me. I would agree with Dr. Gay’s stance on momentum at the goal-line when he states that the offense has the advantage because they are better able to build momentum a hair faster because they know when the ball is going to be snapped, where the defense must anticipate the snap. This falls under the idea when a football coach says, “they’re catching you on your heels.” This is because the offense can get from point A to point B slightly faster than the defense can, ultimately giving the team with the ball the advantage. The greater amount of momentum that one has will overcome a smaller amount of momentum and drive it backwards, in relation to this specific scenario, backwards is the endzone.
The last point of the article in which I would like to touch on is the idea of a ball spiraling in the air towards a player. In high school, I was a receiver and saw this principal in effect everyday from three to six in the afternoon for practice. In my opinion and knowledge of physics thus far, I would say the article does a good job describing a spiral and why it must be thrown hard to keep that tight spiral. The article best sums this idea up by saying “The harder you throw it, the more torque you apply as it leaves your hand, so it spins faster, that means that it’s more stabilized, and you get a tighter spiral.” I believe this is true for short passes and lofted passes as well, even though the article does not address lofted passes. I would like to reflect on this statement and break it down into simpler terms. My best understanding of torque and in my very words is how hard you throw the ball puts more of a spinning or twisting motion on that ball due to the rotation of the hand. With a hard throw and force as we discussed in the first example, it creates more twisting of the ball which in turn keeps it a tight spiral. The idea of a spiraling football in the article and why it spirals has a great explanation by Dr. Gay and in my scientific opinion is quite accurate because the ball has great spin avoiding any air interference that could cause the ball to wobble.
For as great of a job as this article discussed physics and football, I do have one counter argument. It deals with the spiral of a football as I just previously discussed. A statement in the article by Dr. Gay follows, “a ball’s trajectory has much to do with how tight the spiral is.” Trajectory is the flight of the ball to be put simply. I know from past experience playing football that this is not always a true situation, and my encounters with physics thus far have me thinking that it is very possible for a deeply thrown ball to have a spiral. If a player runs deep down field and the quarterback has to loft the ball down field past the defender, it is not always a “wobbly pass.” The Baylor pass didn’t necessarily “fall short of its target,” because of the spiral being wobbly. It was probably more due to the force (push or pull) of the ball and how hard the quarterback threw it or did not throw it to his receiver. Another reason in which a ball may become wobbly is due to the weather conditions and wind. Wind can knock a ball down and thus create a wobble whether it is a short pass or a long pass. So, in conclusion, my only counter argument to this article would be the deep pass of a quarterback and it not being a tight spiral, because I have seen many tight spirals thrown deep down field and completed successfully to the target. Factors such as wind need to be taken into consideration for what makes a ball a tight spiral. Many factors besides air resistance and the spiral itself play an important role on the flight of the football. A tight spiral is also a subjective term, because my idea of a tight ball or wobbly ball may be different that Dr. Gay’s. The explanation of what a tight spiral is or is not should have been more closely addressed.
This article was different from what I believe to be a normal type of physics reading or situation, due to my reading of a textbook. It explained different situations throughout a football game that I as the reader felt were beneficial in my understanding of physics and real world application outside of my classroom. Dr. Gay is a very intelligent physicist and brought forth many engaging examples of physics in the college football world.
Sincerely,
Lucas Wilson
