When a baseball player approaches the plate, he needs physics on his side to score a spot on base. But a rewarding collision between baseball and bat depends on many complicated factors.
One group of researchers from the Sports Science Laboratory at Washington State University explores this complicated relationship between ball and bat, debunking some of Major League Baseball's myths along the way.
As highlighted in a recent article in the American Journal of Physics, balls and bats generally have an inelastic physical relationship, meaning the kinetic energy each has while in motion is not maintained after colliding.
But that certainly doesn't keep people from tinkering with balls and bats to make their partnership more elastic. The key is doing so within the confines of the rulebook, of course.
For instance, when MLB star Sammy Sosa was caught using a corked-filled wooden bat in 2003, it was assumed substituting the core of the bat with a lighter material such as cork allowed players to hit baseballs farther than with typical wooden bats.
But during testing, scientists didn't find this to be true. Instead, they noticed that the balls and bats' coefficient of restitution (COR), or a comparison of the objects' speeds before and after collision, remained similar throughout tests, leaving the energy exchange between the two materials almost the same. There's still, however, another reason players may have a soft spot for corked bats. Because they're lighter, the bats allow players to swing more quickly, which can result in making better contact with the ball and more hits or homeruns in the game. In this case, distance isn't the advantage - swing speed is.
Researchers also compared baseballs from the 1970s to those of 2004 and found little differences between the CORs of the balls, despite claims that modern balls are "juiced" to be more elastic.
The team also assessed whether temperature and humidity affect the physics of the game. Balls placed in controlled humid conditions to deter them from traveling farther at venues such as the high-altitude Colorado Rockies' stadium Coors Field were also studied. Despite other baseball myths coming up short, the team confirmed previous research showing that humidity and temperature lower balls' CORs and slow them down.
Photo by Spitzgogo_CHEN (Nokia 6230i)/Flickr.com Video by Washington State University