I thought I'd take a break from my series on the Large Hadron Collider (see the three previous postings below) to write a mini-review of a book I recently finished reading. The book is The Physics of Basketball, by U.S. Naval Academy professor John Fontanella, himself a former player.
It’s actually more of a lengthy monograph (~130 pages) than a typical book. The book concentrates heavily on the trajectory of basketball shots, both of the “nothing but net” variety and those that bounce around off the backboard and/or rim. Fontanella’s enumeration of all the forces acting on a released basketball shot (e.g., gravity, magnus, drag, and buoyancy) may have some similarity to the talk University of Illinois physicist Alan Nathan presented at last year’s Society for American Baseball Research (SABR) meeting on the aerodynamics of a flying baseball.
Fontanella also addresses a few other issues besides basketball shooting. One is the illusion of "hang time," or a player (former NBA star Gus Johnson being a favorite of the author) who's driving to the hoop "hanging or floating in air, apparently defying gravity and the laws of physics" (p. 121).
The author has a ready explanation for this phenomenon -- a player's initial upward movement is quick, but gravity slows the upward motion. According to a calculation by Fontanella, "a jumping player spends only 29% of the time in the bottom half of the jump. Correspondingly, a player must spend 71% of the time in the upper half of the jump" (p. 122). Thus, we see prolonged periods of a player high in the air.
Another question Fontanella addresses -- for those of you dying of curiosity -- is why you hear so much squeaking of the players' basketball shoes when you're observing from near the court (p. 115).
There’s an online NPR interview (link) with Fontanella you can listen to, which might help you decide if you want to read the book.