Steve Lamoreaux, professor of physics, and a member of Yale’s Wright Lab, explained the physics of the perfect spiral football pass in a clip for PBS’ science program “Nova” that appeared on their Facebook page to coincide with the Super Bowl. The clip can be viewed here.
Lamoreaux worked with Ana Aceves of WGBH, which produces Nova. According to Lamoreaux, they had a long conversation about various aspects of the physics of the phenomenon, and the production team decided to focus on the role of angular momentum as it pertains to the football orientation and trajectory.
Lamoreaux said, “I explained how this affects the quarterback’s stance and motion (arms tucked in so that maximum linear momentum can be delivered to the football). The trajectory is also not a parabola, the horizontal velocity is significantly reduced over the trajectory, so on the downward part of the trajectory it often almost looks like the football is falling straight down into the receiver’s hands.“
Lamoreaux continued, “I told Ana that I noticed these effects when I was 11 or 12, when after the school team’s flag football practice, some of the team would go to the grassy field at the Community Center and play tackle football… We’d take turn with positions, and I was able to throw the ball farther (30 yards +) and more accurately than anyone else. I noticed the effects mentioned above, the orientation change and the closer to vertical drop at the end, and at first I thought it was an optical illusion, but the effect was real.”
According to Lamoreaux, the other academic that appears in the clip is Timothy Gay, the Willa Cather Professor of Physics at the University of Nebraska-Lincoln, who worked at Yale from 1980-83 as a research physicist and lecturer. Gay is the author of the book called “The Physics of Football,” written, Lamoreaux said, “in the spirit of our faculty member Robert Adair’s book on baseball.”
This is the second time that Lamoreaux has explained the physics of football for the media; the first was for ESPN’s NFL countdown in November 2021.