Other Physics of Baseball Links
The Grip Doesn't Matter (new, October 28, 2011): Click on the link to see learn about why the batter's grip doesn't matter during the baseball-bat collision.
Heat-Sensing Camera at the World Series (new, October 20, 2011): At the 2011 World Series, Fox has been using an infrared (IR) camera during its broadcast. Click on the link to read an account of the Adrian Beltre batted ball during the 9th inning of Game #1. Lots of interesting physics going on here and I try to explain some of it in the link.
Home Runs and Humidors: Is There a Connection? an article I wrote for Baseball Prospectus. Be sure to read all the comments. For Coors, the predicted reduction in home runs is 27.5 +/- 4.3 %, in nearly perfect agreement with the actual 25% reduction. For Chase the predicted reduction is 37.0 +/- 6.5 %.
Revisiting Mantle's Griffith Stadium Home Run. A writeup of my reanalysis of The Mick's famous tape measure shot from 1953. An account of this work also appears in Chapter 6 of the new biography of Mantle, The Last Boy, by Jane Leavy, published in October 2010. I gave a public presentation of this topic in Urbana on November 12, 2010 as part of the program of the Baseball Music Project.
How Much Does a Fly Ball "Carry"? Read a brief account on an analysis I did to quantify the term "carry". Included is an analysis of the home runs in the new Yankee Stadium to see if there is any measurable effect of wind.
Baseball at High Altitude Click on this link to learn all about the effect of high altitude on the flight of a pitched or batted baseball.
Baseball Trajectory Calculator (updated, July 16, 2011) Click on the link to download an Excel spreadsheet that can be used to do baseball trajectory calculations, including the effects of air drag, spin and the Magnus force, wind, temperature, and altitude. A glossary has been included, courtesy of Ed Frank. Note that this spreadsheet is changed from time to time, as better models for the aerodynamic effects are developed. The most recent change occured on July 16, 2011, when a new prescription for the drag coefficient was adopted and the possibility of a gyro component to the spin was added.
Bonds 756th home run. My analysis of the trajectory of Barry Bonds' record-breaking 756th home run.
The effect of spin decay on the flight of a baseball.: A brief unpublished essay in which an estimate is made of the rate of spin decay of a baseball in flight and the effect of the spin decay on the flight of a baseball.
Determing the 3D Spin Axis from TrackMan Data (new, September 7, 2011): In this article, I develop a technique to determine the direction of the spin axis for pitched baseballs, utilzing the measurement of the total spin from TrackMan and the magnitude and direction of the spin-induced deflection from the trajectory. An accompanying spreadsheet is a template for the calculations.
Troy Tulowitski's Double Hit: (new, September 8, 2011) Can a batter hit the ball twice in the same swing? Take a look at this remarkable high-speed .avi video from a game on June 25, 2011.
Physics of Baseball and Softball (new, September 7, 2011) by Rod Cross This book, published in March 2011, describes the physics of baseball and softball, assuming that the reader has a basic background in both physics and mathematics. The physics is explained in a conversational style, with words and illustrations, so that the explanations make sense. The book provides an excellent opportunity to explain physics at a relatively simple level, even though the primary objective is to explain the many subtle features concerning the physics of baseball. For those readers who already know quite a bit of physics and who will be comfortable with mathematical equations, additional material of this nature will be provided in appendices. The latest research findings and statistical data have been incorporated by Cross. The book also contains many simple experiments that the reader can perform to convince themselves that the effects described do indeed exist. Cross has written the definitive treatise on the subject and I highly recommend it to all those with an interest in the science of the game.
Physics 199bb A freshman-level course on the physics of baseball given for non-scientists at the University of Illinois during the Fall 2007 semester.
Watch a 50-minute video of my talk on the physics of baseball given March 2002 as part of the Jefferson Laboratory Science Series. The talk can be played on Windows Media Player. The video is the property of Jefferson Laboratory and is posted here with their permission.
How to Hit Home Runs: Optimum Baseball Bat Swing Parameters for Maximum Range Trajectories. The following article appeared in the November 2003 issue of American Journal of Physics and may be found at Gregory S. Sawicki, Mont Hubbard, and William J. Stronge, Am. J. Phys. 71, 1152 (2003) This paper uses improved models for the pitch, batting, and post-impact flight phases of a baseball in an optimal control context to find bat swing parameters that produce maximum range. One of the most interesting findings of the authors is that an optimally hit curve ball will travel farther than an optimally hit fastball or knuckleball due to increased lift during flight. This particular aspect is discussed at length in an NPR broadcast from November 20, 2003. This paper is one of many interesting projects undertaken by Professor Mont Hubbard and his talented students at the Sports Biomechanics Laboratory at UC/Davis.
The Acoustics of Baseball An excellent and very readable report by Professor Bob Adair, based on a talk he gave in June 2001 before the Acoustical Society of America. Another account of this is in the excellent New York Times article by Jim Glanz. Click here for a nifty graphic based on this article. Professor Adair wrote the book entitled The Physics of Baseball, 3rd Edition, which every person serious about the science of the game should read. And speaking about books, you should also check out the book by Watts and Bahill entitled Keep Your Eye on the Ball. Although not as comprehensive as Adair's, it addresses some very interesting issues and give some good explanations based on simple physics principles.
Aerodynamics of the Baseball. These are a series of web sites with information about the flight of a hit or pitched baseball through the air. An excellent site is the NASA-sponsored site Aerodynamics of Baseball, maintained by Tom Benson. Other excellent sites are The K-8 Aerodynamics Textbook and the Baseball Flight Simulator to simulate the flight of a baseball. Check our Brian Raue's site for a study he did of home run distances at Pro Player Stadium. A excellent article, The Mechanics of a Breaking Pitch appeared in the April 1997 issue of Popular Mechanics. Take particular note of the 4th page, which has a very nice description of the physics of a curveball by physicist Peter Brancazio. Finally, check out a nice description of a knuckleball, then watch a short mpeg video of Tim Wakefield in action.
The Juiced Baseball Issue. Is the baseball is "juiced." That is, is it more lively today than yesteryear? Read the account by Rawlings on their manufacturing procedures by clicking here . In 2000 MLB conducted a series of tests on baseballs. Click here to download the official report issued by Prof. Jim Sherwood of the Baseball Research Center at the University of Massachusetts/Lowell, who performed the tests. For a somewhat different take on this issue, see the nice article written by Bill Sloat in the Cleveland Plain Dealer.
Hitting and Pitching Mechanics. Three sites devoted to the mechanics of swinging a bat: Batspeed.com , Coach Preston Peavy's VSI Baseball, and Mike Epstein Hitting. Three sites devoted to the mechanics of pitching a baseball: Tom House, Dr. Mike Marshall, and American Sports Medicine Institute. Both House and Marshall are former MLB pitchers. The ASMI is run by Dr. James Andrews, the surgeon who performs most of the shoulder operations on MLB pitchers.
How Mariano Rivera Dominates Hitters Click on the link to see a NYT story from June 2010 about what makes Rivera the greatest closer in MLB history. Make sure you watch the remarkable video, which was put together using information supplied by the crack analysis team at Complete Game Consulting.
New Technologies in Baseball, a panel discussion of the latest developments in Sportsvision's PITCHf/x, HITf/x and FIELDf/x, and TrackMan's radar technology used to measure ball flight, presented at SABR40 in Atlanta, August 7, 2010. The panel members were Rand Pendleton (Sportvision), Rob Ristagno (TrackMan), Dave Allen (Fangraphs and Baseball Analysts) , Josh Kalk (Tampa Bay Rays), and myself. The zip file contains the talks that were presented by each of us.
Maple vs. Ash: Listen to a podcast of a July 4, 2008 broadcast of NPR Science Friday, hosted by Ira Flatow. Professor Lloyd Smith gives an excellent discussion of the differences between maple and ash bats. See also woodbat.org, a site put together by Roland Hernandez. He gives detailed explanations about wood bats, "slope of grain", ring porous vs. diffuse porous woods, and different failure modes of wood bats.
Hittracker: A web site due to Greg Rybarczyk that reports on home run distances, meaning how far the ball would have traveled had it made it back to ground level without hitting something first. Greg's algorithm is based on his measurement of the precise location where the ball hit and the total flight time, both of which serve as input to his aerodynamic model to extrapolate the trajectory to ground level. The model takes into account drag, lift, and atmospheric conditions. In the absence of additional information about the batted ball, it is the best algorithm currently in use for determining home run distances. Listen to an interview Greg gave on hittracker on October 26, 2011 for 1080TheFan ESPN radio.
Curveballs: When What You See Isn't What You Get, an NPR story from October 23, 2010, including an audio link. Be sure to scroll down to the end of the story and try out the "Curveball Illusion" cartoon. The original paper upon which this story is based may be downloaded by clicking here. The basic premise of the article is that the human visual system peceives motion differently in the central (or foveal) and perpheral parts of the eye. In particular, the peripheral vision can confuse rotational and translational motion. It is argued that this perceived distortion may contribute to a batter's perception that a breaking pitch experiences sudden changes in direction as it approaches home plate. There have been many other news stories (do a search on "curveball illusion") reporting this research. Note that some of the news stories are reporting incorrectly that the authors claim that breaking pitches do not really break. On the other hand, the connection between the illusion in the cartoon and a batter's perception has not been definitely established, nor do the authors claim that it has.
Steroids and Home Run Production. With the admission on January 11, 2010 by Mark McGuire that he used steroids, it is natural to ask what effect that might have on home run production. This question has been addressed in a paper entitled On the potential of a chemical Bonds: Possible effects of steroids on home run production in baseball written by Professor Roger Tobin (Tufts University, Department of Physics) and recently published in the American Journal of Physics. In 2009, I wrote a summary and critique of Tobin's paper that was published in SABR's Baseball Research Journal in Summer 2009. In June 2006, a story appeared online at "ESPN Page 2" by Patrick Hruby that addressed the same issue. I wrote a short set of technical notes at that time (updated Feb. 17, 2009) in an attempt to quantify the effect of increased muscle mass on bat speed.
The Gyroball What's all this gyromania about? To find out, click on the link.
Batting and Thinking. This links to an audio file of a very interesting presentation by Professor Bob Adair given at the Science of Baseball Symposium, part of the AAAS annual meeting in February 2000. He discusses the process whereby a batter observes, processes, decides, and swings the bat. As you listen, you should also look at this excellent graphic , courtesy of the NY Times.
PBS - Scientific American Frontiers. On the Ball: Baseball Tech - watch online as Alan Alda explores the science of baseball. To see the video, click here and scroll down to the Baseball Tech video.
Sites Geared Towards Younger People. The two most important of these sites are (1) Sport Science @ The Exploratorium, the superb site of The Exporatorium science museum in San Francisco, and (2) The K-8 Aerodynamics Textbook, an excellent site put together by Dr. Jani Macari Pallis. The former deals with the physics of baseball, hockey, and other sports. The latter is mostly about aerodynamics, but there is a special section on the physics of tennis. See also Aerodynamic Activities . All these sites are well worth looking at.
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