Since Sammy Sosa has got himself a nice little vacation coming up – albeit, a very expensive one – courtesy of this little stunt, I thought I’d ask if anyone knows of any definitive studies that show whether or not a corked bat does actually affect the distance a ball will fly. I’ve heard both ways, and the “increase of bat speed is cancelled out by the decrease in bat mass” argument has always found a tender place in my heart, but I have to admit to a Conservation of Energy bias in all my thinking, even if I do oversimplify. Ira Flatow once explained how the curve ball curves, but has anyone explained the juiced bat?
This is just a WAG, but the formula for kinetic energy comes to mind: K= mass x velocity squared.
Kinetic energy quadruples if you double the velocity. This is why an M-16 bullet, which has a relatively small mass, can do so much damage. It goes very fast.
I would guess that increasing the mass of the bat would help a bit (if you could get it around fast enough to hit the ball). But it seems to me that increasing bat speed would give you more hitting power.
Anyone care to back this up with real figures, or show me to be mistaken?
This site says it doesn’t help at all, except maybe psychologically.
OTOH, this study (HTML of a PDF from the “director, baseball research center” at U Mass) says that a corked bat will perform 1% better, but will break easily. This is backed up by loads of official sounding data and calculations, so it seems legit.
Man, how do you become the director of the baseball research center? When will they research the degradation of the game due the DH?
Now, IANA phycist, but its been my understanding that the the advantage of using cork in a bat does not have as much to do with less mass leading to greater bat speed as it does with teh inherent springyness of the cork. A corked bat will absorb more kinetic energy from the pitched ball and then release it back into the ball, adding speed and distance to the hit ball.
In fact, putting cork (which is less dense than the ash bats are normally made from) makes the bat lighter, thereby allowing you to swing it faster. Whether it’s enough to make a significant difference or not, I have no idea, and I don’t feel like working it out at the moment. There’s also the matter of elasticity. Hit a marble with a tennis racket and an identical one with a bat. The racket one is going much farther (at least as far as I can recall from doing this as a kid).
Robert Adair, who wrote The Physics of Baseball said that the benefit of corked bats is mainly psychological!
Sammy said he used the bat for batting practice & demonstrations in the Dom Rep, so he must think it gives a little juice. Also, he fanned 6 times this past Sat., so maybe he needed a mental boost, if nothing else. He did say he used the bat by mistake today. As Yogi said, “Ninety % of hitting is mental, the other half is physical.”(Or something like that)
I would think that even if does not increase power, it might increase the ability to get around on the ball, and thus enhance the quality of contact that is made. A little help getting around on a fastball might make it easier to catch it on the sweet spot, but the power still has to come from the batter.
Yes, I am certain he used it by accident.
:rolleyes:
A brief hijack to preach the Gospel of Yogi.
It appears he did, since all of his other bats were clean. ESPN also cited the 1% bat speed increase last night.
In The Physics of Baseball, Robert K. Adair (mentioned above) seems to think that the extra control of the lighter corked bat is more important than the extra speed.
The cork itself doesn’t add to the effect, but in fact detracts from it it. A bat with an empty hollowed out cylinder in the end is just about as strong and as elastic as one filled with cork. The only purpose the cork serves is to avoid the noticeably hollow sound that a bat with an airspace can make when it hits the ball.
Adair has several suggestions for getting the same increase in control by legal means: choke up on the bat, use a shorter bat, use a narrower bat, or use a bat made from a lighter wood. He suggests green ash or black walnut rather than the traditional white ash, though he admits they aren’t as strong.
Lighter wood? I wonder if any major-leaguers use non-white-ash bats regularly? Interesting.
BTW, does MLB have a lower limit on legal bat weight? I know there is an upper limit on how heavy the bat can be.
Barry Bonds, along with a number of other MLB’ers, uses a Canadian-made maple wood bat. Interestingly, the major draw of the maple bat seems to be that they last longer without breaking, not that they give an increase in hitting distance.
Darn, screwed up that coding. Here’s the correct link–interesting article, that.
It seems we have conflicting data - the weight limit applies to how heavy a bat can be, and bats can be lighter (it appears), but players “cheat” by making the bat lighter.
Then there’s that other hypothesis, that a hollowed-out bat is “springier,” causing the bat’s cross section at the point of impact to deform, and then elastically spring back while still in contact with the ball, basically losing less kinetic energy.
But also, it sounds like no one has ever made a halfway scientific study of this*. So who knows?
- I was a judge at a Texas state-wide science fair a couple of months ago. One of the entries from the middle school division was an experiment to see how far bats of different types could hit a baseball. They mounted a the bats on a swivel arm, which a spring rotated to the point of contact, and they measured how far the ball went. The used standard wood bats, aluminum bats, and bats hollowed out and stuffed with different material, including cork. The experiment was good for middle-school kids, but didn’t control for enough variables to be useful to finally settle this question.
Well, aluminum bats sure hit the ball a lot farther, no doubt about that. The difference is enormous.
One of the science-types (I think it was Adair) siad on the air yesterday that the “springiness” factor is BS. In the 1/2000 of a second that the ball is in contact, the wood has time to deform and return its energy to the ball, but the mushier corking substance does not. While it may be springier, under actual working conditions, the energy is dispersed well after it could be of help.
Here’s a link to an article in the San Francisco Chronicle about a study done by engineers at the University of Massachusetts Baseball Research Center:
They did tests of corked versus uncorked bats, and concluded that a fly ball hit with a corked bat goes about two percent farther. There are two reasons: the bat is lighter, giving increased bat speed, and the hollowed bat is springier, producing a “trampoline effect.” The main reason for filling the bat with cork is to muffle
the characteristic “boom” sound of a hollowed bat, which is
different enough from the “crack” of a normal bat that it could lead to the cheater being caught.
The article has a small illustration at the top. If you click on it, it will bring you to an enlarged version of the illustration that summarizes the article.