Re: [OT] Simple math considered physics; turns out it's fun, not harmful
On Nov 21, 2007, at 17:51, Greg Rundlett wrote: > That's fast. It's also faster than the guy said. He said it was > supposed to be somewhere in the 70 mph range. > Perhaps the numbers are off. Perhaps it's more than a physics problem (likely it's still a math problem). My guess is it's more of a neuroscience problem than anything, if you want to get into MLB equivalents. What percentage of the pitch time is reaction time? How fast do signals travel along the involved neuronal pathways? How long does it take the brain to calculate a trajectory and hitting solution? Whatever the numbers are, they'll figure into how 'fast' the ball feels. Rather than calculate it, it's probably easier and more accurate to ask a bunch of pro hitters to swing and say about how fast the ball feels to them. "About 70" might be a reasonable answer. Or the guy at the cages might have totally made that up. :) There's a trick with some (all?) spiders you can play where you try to touch them and they move out of the way before your hand moves. Really? No, but their neurons are much faster and shorter than yours, so by time you get your brain into gear and move your hand and see the result, the spider has seen and reacted, and it looks to you like he has 'spidey sense'. That is, your hand is moving before you realize it, because there's a delay in your perception. It's tough that we have to make judgments about the Universe with this crude matter. If somebody is really interested there are FMRI studies that have timed these intra-brain signals. -Bill - Bill McGonigle, Owner Work: 603.448.4440 BFC Computing, LLC Home: 603.448.1668 [EMAIL PROTECTED] Cell: 603.252.2606 http://www.bfccomputing.com/Page: 603.442.1833 Blog: http://blog.bfccomputing.com/ VCard: http://bfccomputing.com/vcard/bill.vcf ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Simple math considered physics; turns out it's fun, not harmful
On Nov 21, 2007 11:03 PM, Greg Rundlett <[EMAIL PROTECTED]> wrote: > > Philosophically and sociologically, I'm asking why somebody who worked > there wouldn't solve these problems out of curiosity. Because they > don't know how? Because they don't care? Because they were > conditioned by social norms to believe the subject is too difficult or > uncool? > I went to an engineering college. Most of my classmates would probably take a stab at the problem. Many of my IT colleagues might also. The facilities guys, the administrative assistants, the cafeteria staff, etc would probably not. Most people are not "problem solvers" and it's a personality thing. I bet most of us on this list took things apart as kids to see how they worked. That's what this physics problem is: taking it apart to see how it works/compares. Most people don't do that. ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Simple math considered physics; turns out it's fun, not harmful
Brian Chabot wrote > In terms of education and its promotion, it might be interesting > to use baseball physics to get students more interested who > otherwise might not be... It's an opportunity that's being pursued. As one example there's a book specifically about baseball, http://www.aapt.org/Store/description.cfm?ID=NB-37&Category=All&Type=All&Level=All&Keywords= There are a number of others. Sometimes special courses are offered on such topics, intended for students who might not realize how much fun physics really is. cgm ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Simple math considered physics; turns out it's fun, not harmful
On Wednesday 21 November 2007 17:51, Greg Rundlett wrote: > I really like the indoor batting facility in Salisbury, MA (Extra > Innings). I wondered how 'fast' the fast cage was > Y = Big League pitch speed = > 60.5 feet / .45 seconds = Y feet / 1 second > Y = 134.444 feet / second * 3600 / 5280 = 91.66 mph I did figure it out - approximately. The Reynold's number is 18, assuming the ball is a smooth sphere of 70mm diameter (I didn't look up the actual size). The drag coefficient is .5, which results in a retarding force of 1.8 Newtons. The drag reduces the energy of the ball by 34 joules in its flight from the mound to plate (taken as 19 meters). The energy of the ball when crossing home plate is 160J, assuming a weight of 200 grams (which I didn't look up either). That means the initial velocity must be 44m/s to arrive at the plate at 40m/s (90mph). So, the hydrodynamic drag is not very significant. Using the average speed, my calculations show you would have .435 seconds to react. So, congratulations on your fast reflexes! And, it goes to show how enlightening even an approximate calculation can be. Or, more particularly, that an approximate calculation is often close enough. The fancy physics is not needed. Insidently, the drag force drops suddenly by a factor of 2 just above 90mph. Thus, a 92mph pitch would arrive in perhaps .40 seconds. Pitching just above or just below that change must be some part of making those big league pitchers so hard to hit. Jim Kuzdrall ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Simple math considered physics; turns out it's fun, not harmful
> If you're asking how fast does it appear to be going based on > time of flight from the pitchers mound to the batter, the answer > is 100mph. Heh. And I wonder if the insurance premiums aren't a bit more affordable if you explain to your insuror that you're only beaning your customers with ~50mph projectiles instead of ~100mph ones... ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Simple math considered physics; turns out it's fun, not harmful
The real physics (1960's vintage, no calculators, no linux) answers (plural) are even simpler. If you're asking how fast is the ball going, it's going 50mph. If you're asking how fast does it appear to be going based on time of flight from the pitchers mound to the batter, the answer is 100mph. 60.5' is about double the actual 33' over which the ball is being pitched in the batting facility. If the ball is to cover twice the distance in the same time, it must be going twice as fast. I agree that my estimate of doubling distance is about 10% off so the ball would actually only appear to be going about 90mph. That's still not accurate to 4 significant figures, but we're looking for the physics solution, not the engineering solution (you've heard the one about the physicist, engineer and mathematician whose houses caught fire) and I doubt most batters could tell the difference between a 90mph and a 91.66mph pitch. Mike Miller - Original Message - From: "Greg Rundlett" <[EMAIL PROTECTED]> To: "GNHLUG" Cc: "Geoff Rundlett" <[EMAIL PROTECTED]> Sent: Wednesday, November 21, 2007 5:51 PM Subject: [OT] Simple math considered physics; turns out it's fun, not harmful >I really like the indoor batting facility in Salisbury, MA (Extra > Innings). I wondered how 'fast' the fast cage was. It seemed really > fast and has taken me a few visits to get to the point where I can hit > the ball. I asked today how fast the machine was. The friendly staff > person told me it pitches at 50mph and the machine is 33ft. from the > plate. A regular pitcher's mound is 60.5 ft from the plate. He said > if I have some friends who know physics I could figure out how fast > that is in the big leagues. I'm not making fun of the guy, but > physics isn't involved in solving the problem, just regular math. > > nb: there are 5,280 feet / mile > > spoiler: the answer is below. If you want to figure it out for > yourself, stop here for a bit. > > > > > > > > > > > > > > anser below. > > > > > > > > > > > > > > > > > anser below. > > > > > > > > > > > > > 'fast' batting cage speed > 50 miles / 1 hour = 264,000 feet / 3,600 seconds = 73.333 feet / second > X = elapsed time to home plate = > X seconds / 33 feet = 1 second / 73.333 feet > 73.333X = 33 > X = .45 seconds > > Y = Big League pitch speed = > 60.5 feet / .45 seconds = Y feet / 1 second > Y = 134.444 feet / second * 3600 / 5280 = 91.66 mph > > > That's fast. It's also faster than the guy said. He said it was > supposed to be somewhere in the 70 mph range. > Perhaps the numbers are off. There is another 'VERY fast' cage that > supposedly throws 60mph and is slightly further away (like 33.5 feet). > > I don't know whether I should be happy (I am) that I can hit the > equivalent of a 91mph fastball. Or, if I should be sad that an > average person might think that there is physics rather than math > involved. > > -- > A: Yes. >> Q: Are you sure? >>> A: Because it reverses the logical flow of conversation. >>>> Q: Why is top posting annoying in email? > ___ > gnhlug-discuss mailing list > gnhlug-discuss@mail.gnhlug.org > http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/ > ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Simple math considered physics; turns out it's fun, not harmful
Greg Rundlett wrote: > Philosophically and sociologically, I'm asking why somebody who worked > there wouldn't solve these problems out of curiosity. Because they > don't know how? Because they don't care? Because they were > conditioned by social norms to believe the subject is too difficult or > uncool? I'm actually quite surprised no one did. > The science of physics is certainly involved in this situation; you > can't escape physics in a physical world. If I thought about the > problem from more of a physical perspective, then I'd wonder if > air-resistance and distance factored into the two scenarios to create > any difference. Is there a (marked) difference in deccelleration > (initial velocity - final velocity) between the two environments due > to the almost double distance traveled by a major-league fast ball? [snip questions] There is, as you said, a small influence of the ball falling due to gravity, which I would expect to be a minor but present influence on the velocity. A comparison between the effects of gravity and of air friction would be interesting, as would any lift or other forces generated by a spin on the ball. > There is a lot more math involved, but I don't know those equations or > models. I certainly don't know how to model the aerodynamics of a > dimpled ball relative to a stitched baseball, and I guess for > practical purposes I'm happy to not care. It shouldn't be too difficult to calculate given a good experimental situation -- something any AP or college physics student could easily come up with. (Finding the acceleration and/or terminal velocity of a falling ball in a given atmospheric condition and calculating from there comes to mind.) > I bet there is a lot going on > in Free Software to help physical scientists and mathematicians solve > complex problems My guess is that ballistics software would help more than aerodynamic modeling software in this case because of the trajectory and other factors involved. Also, to bring this more on topic, as a push for FOSS, with open source software you could use available source code for ballistics and aerodynamic modeling in order to find the exact answer here. In a closed source world, you'd have to start from scratch... In terms of education and its promotion, it might be interesting to use baseball physics to get students more interested who otherwise might not be... Brian ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Simple math considered physics; turns out it's fun, not harmful
I just offer an interesting example of how math ain't that hard, and can be used to solve "fun" problems. The basic question at hand was "How fast does the machine pitch? (compared to a major-league pitcher)". The basic answer could be found through some unit conversion and cross multiplication. I didn't need a calculator to figure it out, I just wrote it down on a piece of paper. Aside: One thing that I enjoyed about being a carpenter back in college was that I used math all the time to solve interesting problems with a pencil and a scrap of wood. Philosophically and sociologically, I'm asking why somebody who worked there wouldn't solve these problems out of curiosity. Because they don't know how? Because they don't care? Because they were conditioned by social norms to believe the subject is too difficult or uncool? The science of physics is certainly involved in this situation; you can't escape physics in a physical world. If I thought about the problem from more of a physical perspective, then I'd wonder if air-resistance and distance factored into the two scenarios to create any difference. Is there a (marked) difference in deccelleration (initial velocity - final velocity) between the two environments due to the almost double distance traveled by a major-league fast ball? Does a fast ball even slow down in that short of a distance? Also, how does the trajectory compare? A pitch comes from a pitcher on a mound. Is the ball machine at a similar elevation in relation to the batter? I theorize that a dimpled plastic practice ball travelling 33 feet travels more linearly than a major-league two-seam fastball travelling 60.5 feet, but maybe there is no difference in trajectory. There is a lot more math involved, but I don't know those equations or models. I certainly don't know how to model the aerodynamics of a dimpled ball relative to a stitched baseball, and I guess for practical purposes I'm happy to not care. Maybe the space-time warp created by the massive concrete floor has an effect compared to the relatively light sod at Fenway I bet there is a lot going on in Free Software to help physical scientists and mathematicians solve complex problems All math and physics put aside, I know this much. I am 41 years old. The fact that I can hit a fast ball in the cages doesn't make me eligible to try out for the Red Sox. I guess I'll keep my day job and look for fun wherever I can find it :-) ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Simple math considered physics; turns out it's fun, not harmful
On Wednesday 21 November 2007 17:51, Greg Rundlett wrote: > He said if I have some friends who know physics I could figure out > how fast that is in the big leagues. I'm not making fun of the guy, > but physics isn't involved in solving the problem, just regular math. Actually, it is a physics problem. Assuming the ball velocity is measured at "home plate", the ball is likely to have left the pitcher's hand at a considerably higher speed than it has at the end of its travel. With the Reynold's number for the baseball and some well accepted flow models, the "flow regime" can be determined. I would guess it is in the velocity cubed region. That means drag forces are proportional to velocity cubed, and thus the speed may vary considerably during its travel. Again, subject to a rather straight forward computational confirmation. If the ball is slowing down significantly, it must be going quite a bit faster at 33 feet, and even faster at 60 feet. Which means that the travel time (batter response time) is shorter for a 96mph pitch than you calculated by the linear speed approximation. In fact, intuitively the 70mph guess might be about right. Anyway, congratulations for turning to some math (and physics) for an initial guess. Very often, particularly in engineering, such approximations are good enough to whittle choices down to only one (or none), making the more sophisticated computation unnecessary. And it gives more insight than a blind guess. And fun. The difference between pure math, applied math, and physics is probably too OT for this forum. But interesting. Jim Kuzdrall ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Simple math considered physics; turns out it's fun, not harmful
On Nov 21, 2007 6:07 PM, Bill Ricker <[EMAIL PROTECTED]> wrote: > > that is in the big leagues. I'm not making fun of the guy, but > > physics isn't involved in solving the problem, just regular math. > > Physics is just applied math. All the world is functions. > > -- > Bill > > <[EMAIL PROTECTED]> Speaking strictly as a physicist, I respectfully disagree with that statement. -Mike- -- "America is at that awkward stage. It's too late to work within the system, but too early to shoot the bastards." --Claire Wolfe ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Simple math considered physics; turns out it's fun, not harmful
On Nov 21, 2007 5:51 PM, Greg Rundlett <[EMAIL PROTECTED]> wrote: > Or, if I should be sad that an average person might think that > there is physics rather than math involved. Physics was involved. Indeed, you just solved a physics problem. The fact that you used math doesn't mean it wasn't a physics problem. You also probably used English to talk to the guy; that doesn't mean it was an English problem, either. Or maybe it was; after all, if you didn't know English, it wouldn't matter how good your math and physics skills were, because you wouldn't have been able to get the needed information from the guy. Related: An interesting point to ponder is: What problem did you really solve? You figured the time it took for the ball to travel from "pitcher" to plate, and from that figured how fast the ball would have to be going to travel the same distance in the same time on an MLB field. But is that really the same thing as a real MLB pitcher's fastball? I suspect not. :) But *that's* more about biology and human-factors than either math or physics. Huh. Maybe there is something to this "education" thing after all. ;-) -- Ben ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Simple math considered physics; turns out it's fun, not harmful
> that is in the big leagues. I'm not making fun of the guy, but > physics isn't involved in solving the problem, just regular math. Physics is just applied math. All the world is functions. -- Bill [EMAIL PROTECTED] [EMAIL PROTECTED] ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
[OT] Simple math considered physics; turns out it's fun, not harmful
I really like the indoor batting facility in Salisbury, MA (Extra Innings). I wondered how 'fast' the fast cage was. It seemed really fast and has taken me a few visits to get to the point where I can hit the ball. I asked today how fast the machine was. The friendly staff person told me it pitches at 50mph and the machine is 33ft. from the plate. A regular pitcher's mound is 60.5 ft from the plate. He said if I have some friends who know physics I could figure out how fast that is in the big leagues. I'm not making fun of the guy, but physics isn't involved in solving the problem, just regular math. nb: there are 5,280 feet / mile spoiler: the answer is below. If you want to figure it out for yourself, stop here for a bit. anser below. anser below. 'fast' batting cage speed 50 miles / 1 hour = 264,000 feet / 3,600 seconds = 73.333 feet / second X = elapsed time to home plate = X seconds / 33 feet = 1 second / 73.333 feet 73.333X = 33 X = .45 seconds Y = Big League pitch speed = 60.5 feet / .45 seconds = Y feet / 1 second Y = 134.444 feet / second * 3600 / 5280 = 91.66 mph That's fast. It's also faster than the guy said. He said it was supposed to be somewhere in the 70 mph range. Perhaps the numbers are off. There is another 'VERY fast' cage that supposedly throws 60mph and is slightly further away (like 33.5 feet). I don't know whether I should be happy (I am) that I can hit the equivalent of a 91mph fastball. Or, if I should be sad that an average person might think that there is physics rather than math involved. -- A: Yes. > Q: Are you sure? >> A: Because it reverses the logical flow of conversation. >>> Q: Why is top posting annoying in email? ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/