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Sosa's Bat - Physics Quiz?!(18 posts)

Sosa's Bat - Physics Quiz?!jose_Tex_mex
Jun 5, 2003 12:58 PM
I really do not see all of the fuss about Sosa's Bat. In fact, IMHO, I think as a power hitter her really hurt himself.

True, he broke the rules of baseball and should be dealt with. However, I am more interested in the Physics of the corked bat.

If Sosa was involved in a hitting streak then things would be different. However, he's a power hitter and corked bats don't help.

Here's my analysis.
Home run hitters want a high bat speed and rigid bat. This combination will maximize compression/deformation of the baseball. This is potential energy which will quickly be turned in to Kinetic.

If you drill the bat out and insert cork you increase the bat speed but decrease the mass/rigidity. Thus, batters will catch up to the fastball and get more hits. However, the distance these balls are batted decreases.

Without getting in to a discussion of the natural harmonics of the bat, we can say that the impact time of the ball on the bat is much smaller than any rebound that can occur due to cork.

So then what's the problem?
wrongmohair_chair
Jun 5, 2003 1:05 PM
Have you ever tried to stick a cork back in a wine bottle? Ever tried to crush one? It's very rigid stuff. Cork is lighter and equally or not much less rigid than the removed wood. Ergo, you get a more appealing bat.

The question in this case is why he felt he needed to hit the ball 550 feet instead of just 500.
Huh?czardonic
Jun 5, 2003 1:37 PM
If you think that cork is hard to get back into a bottle, try jamming a plug of pine the same size in there.

Better yet, try hitting a home run with an 100% cork bat.
yeah, huh?mohair_chair
Jun 5, 2003 1:57 PM
first of all, pine is far too soft a wood to make a decent bat out of. typically they use ash. I probably could jam a plug of pine in a bottle.

secondly, your response shows you clearlydon't get the concept. the rigidity of cork, and the reason why they stick it in bats (and bottles), comes from its resistance to compression. it has little resistance to other forces, like torque, which is why no one builds bats out of cork.

the ideal way to cork a bat is to drill out a cylinder of ash and replace it with an oversized cylinder of cork. jam it in with a mallet to put the cork under maximum compression. just like a bottle, although you might be partial to wine with convenient screw top, or maybe even wine that comes in a box.
If you can jam a pine plug into a wine bottle. . .czardonic
Jun 5, 2003 2:11 PM
. . .I will concede the point.

I certainly don't understand the concept of cork's rigidity. Seems to me that every application of cork relies one its flexibility and compliance, not on its stiffness.

Thanks for setting me straight.
Actually it would go about 3 feet less..Brooks
Jun 5, 2003 2:52 PM
according to some scientist I heard on the radio. Corked bat= lighter bat, faster swing, less power. So it is great for punch and judy hitters (Pete Rose) because it gives them a fraction more time to wait and see when the pitch is going to do, but it is silly for power hitters (Sosa).
Agreed nmjose_Tex_mex
Jun 6, 2003 8:20 AM
Why can't we give him the benefit of the doubt?Kristin
Jun 5, 2003 3:22 PM
He claims that he picked up the wrong bat. Very few athletes I would believe and certainly this is suspicious. But for some reason I do believe him. So do most Chicagoans. He has never come across to me as the type that would cheat. I could be niave, but I'm giving him the benefit of the doubt.

But I know nothing about baseball. Can a pro player tell the difference between a cork bat and a wooden bat just by picking it up? In other words, is his story a lame duck?
The wrong bat?jtolleson
Jun 5, 2003 3:59 PM
Why would a professional athlete with fine tuned skill sets like trying to hit a 90 mph fastball want to practice with a bat that is not game legal? I just found it hard to believe that a hitter would want to take BP with one kind/weight of bat and use a different one at game time. Seems to me that if a player is going to drill a bat out and cork it, their whole intention MUST be to use it in competition.

Yes, I've been hearing the theories that corking is for singles hitters, not power hitters, but most of those who have been caught have been middling power hitters (HoJo, Chris Sabo, Billy Hatcher) though not dominating home run kings.
As I say to students Mohair, convince yourself...jose_Tex_mex
Jun 6, 2003 8:18 AM
Dear Mohair,
You might want to try and turn down your contempt for others on the board, especially in light of a posting which is off on so many levels I do not know where to start. FWIW - I think you owe Czardonic an apology.

Since I know the last thing on earth you will ever do is agree with my conclusions, I have supplied a few links.

Here's an experiment done by a seventh grader which disagrees with your arguement.
http://www.youth.net/nsrc/sci/sci060.html

Here's a link from Yale professor and author of "The Physics of Baseball" - Robert K Adair - again disagreeing with your assessment. http://www.bostonbaseball.com/whitesox/baseball_extras/physics.html

An interview with Adair
http://www.ajprint.net/archive_authors/canfield/interview.html

Another from NIST a blurb http://www.100.nist.gov/battampering.htm

As for your arguement, what can I say? You suggest that cork is "rigid stuff?!" Then you cite it's ability to be densely packed. Wow! Do you not see the problem here?

Rather than address the rest of your "points" I will just restate what most accredited Physicsts believe.

When a baseball is struck there is a very small amount of time in which the bat contacts the ball. During this time the ball is deformed and gains potential energy (transferred by the batter's rotational and translational velocities). This potential energy is then converted into Kinetic. The harder the bat the more the ball is "squished." The faster the hard bat - even more squish.

The major error here is that you fail to realize the impact contact time for the collision is far too short for the "springiness" of the cork to give back any energy it may have gained. See the natural frequency discussion above with Adair.

As it turns out, by corking the bat you decrease the rigidity of the bat. Thus, the hardness of the bat is decreased and there is less energy stored in the ball during impact.

This is bad for Sosa (long ball hitter). However, good for streak hitters like Pete Rose. Need to catch that fast ball? Well a lighter bat "could" help.

When it comes to bat speed vs bat rigidity for homeruns, what you make up in speed is far outweighed by what you lost in rigidity.

QED
From what I have read ....Live Steam
Jun 5, 2003 1:42 PM
it has never been shown one way or the other that a "corked" bat is of any benefit. The link below has a reasonable explanation.

http://www.signonsandiego.com/sports/baseball/20030605-1029-sosasbat.html
You're probably right. But what would Baseball be. . .czardonic
Jun 5, 2003 1:58 PM
. . .without these fusses and pedantic technical debates?

I predict that Baseball will eventually be replaced entirely by it fantasy counterpart, with stats fed by a computer model.
You misheard. Sosa was using a quarked bat, not corked.carnageasada
Jun 5, 2003 2:36 PM
The combination of the quark and the bat was illegally maximizing/annhilating the compression/deformation of the baseball.
"Up" quark bats for fly balls, "down" quark bats for groundersStampertje
Jun 6, 2003 9:10 AM
"Charm" quark bats for picking up chicks after the game.
quantum humor; we are a bunch of geeks, huh? nmDougSloan
Jun 6, 2003 10:16 AM
Pick up chicks? You mean, get some 'strange' quarks? nmOldEdScott
Jun 6, 2003 10:47 AM
As I understand it.Spoke Wrench
Jun 6, 2003 8:25 AM
Replacing part of the wood with cork allows you to have a bat that weighs the same but has a larger diameter. Consequently, you get the bat speed of a lighter bat with the larger "sweet spot" of a fatter, heavier bat.
Right53T
Jun 6, 2003 11:53 AM
Like an aluminum bat, which we all know is superior, due to its light weight, high rigidity and "correct" dimensions. Tubular construction is always better (do you see any solid tube bike frames around?) A corked bat is a tubular ash bat. It's better, but it's against the rules.