Re: [OT] Simple math considered physics

2007-11-26 Thread Bill McGonigle
On Nov 22, 2007, at 21:18, Drew Van Zandt wrote:

 I'm sure you can't MAKE kids interested in engineering, but there are
 certainly classes of toys that a great many of the more geek- 
 inclined people
 I know remember fondly.

I'm largely siding with nature on this one.  I had our two kids down  
in the basement play-area yesterday and the older one was showing me  
her ballet moves and such, while the younger one was ignoring his  
baby toys to try to figure out how the tensioner was keeping the  
chain on my 10-speed taught.

Now, the girl is quite good at science - she was answering some of  
the astronomer's questions about the moon's formation when we went to  
viewing night at the planetarium - but she sees science as a means to  
an end.  She's planning on being either a teacher or veterinarian  
(undecided) on the moon when she grows up.  She's more of a  
scientist, science is a tool for discovery.

The boy just likes to take everything apart and figure out how they  
work - he's more of the engineer.

I did nothing intentional to differentiate the two - no nurture  
there, but odds are we'll give the boy more geek toys than the girl  
(her OLPC on-order, excepted), so perhaps one nurtures the nature  
inherent.

Of course, they both like to take cardboard boxes and re-purpose them  
to more exciting uses - a kid who lacks this interest might need to  
be sent in for inspection - so basic hacking is innate in most  
humans, some are just suppressed at an earlier age than others.

 Any I've missed?  If I ever have children they're definitely going  
 to have
 easy access LEGO and random electronic components.

As Ben mentioned Capcella are really neat - I had them as a kid too.   
I suspect this may be related to why we both dumped Slackware for  
Redhat.   Oops, sorry, on-topic.

I learned my basic chemistry in order to make things that exploded,  
sometimes with attached payloads.  I learned some social engineering  
in order to acquire supplies for said experiments.  When at first the  
town pharmacist calls your folks for trying to buy saltpeter one must  
devise alternate tactics. ;)

 (Books too, of course, but like many a young child that goes without
 saying.)


As alluded to by others, the entire line of Boy Scout books is very  
useful for introductory material to myriad topics.  Tom Brown's  
guides were also very helpful for more in-depth hacking of nature.

-Bill

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Re: [OT] Simple math considered physics; turns out it's fun, not harmful

2007-11-26 Thread Bill McGonigle
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

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Re: [OT] Simple math considered physics

2007-11-25 Thread Jeffry Smith
On 11/24/07, Jon 'maddog' Hall [EMAIL PROTECTED] wrote:

 That book (unfortunately) has been out of print for many, many years,
 but here is another book along the same lines that I would recommend:

 http://www.amazon.com/American-Boys-Handy-Book-Nonpareil/dp/0879234490/ref=si3_rdr_bb_product

 a reprint of Dan Beard's book: The American Boy's Handy Book: What to
 Do and How to Do It  While Lord Baden-Powell was the originator of Boy
 Scouts, Dan Beard was the movement's heart.

Not quite - Dan Beard was heavily involved in the BSA (Boy Scouts of
America) development, but most of the UK Scouting (the original home
of scouting) was based on Lord Robert Baden-Powell's Scouting for
Boys - which was a version of his original Aids to Scouting written
for the British Army, written after he saw youth in Britain using
Aids to Scouting, and tested in 1907 by Lord Baden-Powell at
Brownsea Island as he developed the original Scouting program.  This
original work did include ideas from Ernest Thompson Seton, Dan Beard,
and others, so in that respect Mr. Beard had influence on the Scouting
Movement as a whole.

Later, when W.D. Boyce discovered scouting and brought it to the US,
Dan Beard  Ernest Seton were key leaders in the movement.
(http://www.boyscoutstuff.com/text.html) .


 Not to be outdone, there was a companion book for girls published by his
 wife:

 http://www.amazon.com/gp/product/0879236663/ref=pd_luc_215881650940879236663

 actually, the set would be good for any family.

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Re: [OT] Simple math considered physics

2007-11-24 Thread Michael Costolo
On Nov 23, 2007 10:01 PM, Jon 'maddog' Hall [EMAIL PROTECTED] wrote:

 but here is another book along the same lines that I would recommend:


 http://www.amazon.com/American-Boys-Handy-Book-Nonpareil/dp/0879234490/ref=si3_rdr_bb_product

 a reprint of Dan Beard's book: The American Boy's Handy Book: What to
 Do and How to Do It  While Lord Baden-Powell was the originator of Boy
 Scouts, Dan Beard was the movement's heart.


Likewise is The Dangerous Book For Boys.  A book my boy just got from his
grandfather.

http://www.amazon.com/exec/obidos/ASIN/0061243582/bookstorenow99-20

-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
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Re: [OT] Simple math considered physics

2007-11-24 Thread mike miller
Great book.  Also check out the magazine MAKE.

Mike
  - Original Message - 
  From: Michael Costolo 
  To: [EMAIL PROTECTED] 
  Cc: gnhlug-discuss@mail.gnhlug.org 
  Sent: Saturday, November 24, 2007 5:59 AM
  Subject: Re: [OT] Simple math considered physics





  On Nov 23, 2007 10:01 PM, Jon 'maddog' Hall [EMAIL PROTECTED] wrote:

but here is another book along the same lines that I would recommend:


http://www.amazon.com/American-Boys-Handy-Book-Nonpareil/dp/0879234490/ref=si3_rdr_bb_product
 

a reprint of Dan Beard's book: The American Boy's Handy Book: What to
Do and How to Do It  While Lord Baden-Powell was the originator of Boy
Scouts, Dan Beard was the movement's heart. 


  Likewise is The Dangerous Book For Boys.  A book my boy just got from his 
grandfather.

  http://www.amazon.com/exec/obidos/ASIN/0061243582/bookstorenow99-20 

  -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 


--


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Re: [OT] Simple math considered physics

2007-11-23 Thread Jon 'maddog' Hall
 Any I've missed?  If I ever have children they're definitely going to
 have easy access LEGO and random electronic components.

Rubber-band powered airplanes made of balsa and tissue paper (today the
tissue paper is sometimes replaced with ultra-thin plastic, which can
actually be made by spreading liquid plastic on top of water).  This is
not just a kid thing, as many adults like building these too.

Small radio-control units can now be purchased for a small amount of
money and re-used over and over again if the plane (or boat or car)
lands right (or even at all).

For that matter, paper airplanes have many designs, and orgami is a
great art to practice, as you can entertain people at almost any time
with a few scraps of paper.

And kites made from bamboo and paper.  Start them now and use them this
spring.

All of these flying, floating things need physics and math.

Many years ago Popular Mechanics published a book called The Boy
Mechanic that had hundreds of pages of projects from the very simple to
the very complex of things for children to build from everyday
components.  When I was in grade school I borrowed the book many times
from the library, and eventually bought a used copy when I was in
college.

One project, however, was how to build a hot-air balloon out of tissue
paper.  From personal experience I recommend adult supervision on that
one

That book (unfortunately) has been out of print for many, many years,
but here is another book along the same lines that I would recommend:

http://www.amazon.com/American-Boys-Handy-Book-Nonpareil/dp/0879234490/ref=si3_rdr_bb_product

a reprint of Dan Beard's book: The American Boy's Handy Book: What to
Do and How to Do It  While Lord Baden-Powell was the originator of Boy
Scouts, Dan Beard was the movement's heart.

Not to be outdone, there was a companion book for girls published by his
wife:

http://www.amazon.com/gp/product/0879236663/ref=pd_luc_215881650940879236663

actually, the set would be good for any family.

Like music?  Go beyond just the ipodget an old 78 record and show
them the grooves.  Pluck a string and show them the harmonics.  Get them
involved with midi, electronic music.  Lots of cool software for audio
on Linux.

md
-- 
Jon maddog Hall
Executive Director   Linux International(R)
email: [EMAIL PROTECTED] 80 Amherst St. 
Voice: +1.603.672.4557   Amherst, N.H. 03031-3032 U.S.A.
WWW: http://www.li.org

Board Member: Uniforum Association
Board Member Emeritus: USENIX Association (2000-2006)

(R)Linux is a registered trademark of Linus Torvalds in several
countries.
(R)Linux International is a registered trademark in the USA used
pursuant
   to a license from Linux Mark Institute, authorized licensor of Linus
   Torvalds, owner of the Linux trademark on a worldwide basis
(R)UNIX is a registered trademark of The Open Group in the USA and other
   countries.


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Re: [OT] Simple math considered physics

2007-11-23 Thread Jim Kuzdrall
On Thursday 22 November 2007 21:18, you wrote:
 I'm sure you can't MAKE kids interested in engineering, but there are
 certainly classes of toys that a great many of the more geek-inclined
 people I know remember fondly.

 LEGO
 Erector sets
 Tinkertoys
 Lincoln Logs
 Piles of junk + imagination

 Any I've missed?  If I ever have children they're definitely going to
 have easy access LEGO and random electronic components.

I had the last 3 of the above.  LEGOs weren't invented, and we 
couldn't afford the Erector set.  I did get a hand-me-down electric 
train and used 5-tube table radio though.  You might guess the source 
of my ham radio interests.

Two areas that you might consider when expanding your list are 1) 
things to extend the child's senses, and 2) stuff to take apart.

I never got a microscope, but tried to build one.  A binoculars led 
to many summer nights on the lawn matching constellations to those in 
my book, watching meteors, and hoping to spot a UFO.  (The binoculars 
had an eerie story with them.  My father had taken them from a dead 
French officer in the Pacific.  There was blood on the leather case.)

Before things were junked (which was seldom), they were offered to 
us to take apart.  I remember getting a wind-up alarm clock at age 4.  
The brass gears were fascinating.  And frustrating, because there was 
nothing I could do with them.

My mother was usually neutral about taking things apart.  Usually.  
My younger sister had an expensive doll that gave out a Whaaah sound 
when tipped over.  My brother and I convinced her that her baby would 
not be crying unless there was something wrong with it.  So, my good 
hearted sister gave permission to operate.  My mother was not 
pleased.

Jim Kuzdrall
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Re: [OT] Simple math considered physics; turns out it's fun, not harmful

2007-11-22 Thread Jim Kuzdrall
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
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Re: [OT] Simple math considered physics; turns out it's fun, not harmful

2007-11-22 Thread Michael ODonnell


 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...
 
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Re: [OT] Simple math considered physics; turns out it's fun, not harmful

2007-11-22 Thread mike miller
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 gnhlug-discuss@mail.gnhlug.org
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?
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Re: [OT] Simple math considered physics; turns out it's fun, not harmful

2007-11-22 Thread Charles G Montgomery
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-37Category=AllType=AllLevel=AllKeywords=

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
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Re: [OT] Simple math considered physics

2007-11-22 Thread Jim Kuzdrall
On Thursday 22 November 2007 12:01, Ric Werme wrote:

 Sigh, one course I didn't take in college and kinda wish I had was
 Fluid Dynamics.  I really should read up on that.  I did show some
 movies in a FD class showing turbulent  laminar drag.

I took Fluid Mechanics at Michigan Tech (in the UP) in the summer 
after my freshman college year.  It was very different from the 
abstract symbolic solutions that were favored at MIT.  I think I wore 
out a slide rule converting head-feet-of-kerosene to psi etc.  We had 
to do 15 problems a week, at least one being s stumper to try prevent 
there being any 100% papers.  (And nobody would even consider sharing 
work back then - you were there to learn as an individual, not as a 
group.)

Several things of lasting value came from the course besides knowing 
how wide to dig ditches.  I am confident that I can convert any units 
the world wants to work with.  And, I learned the value of doing a 
dimensional analysis on the equations.  If the equation is calculating 
pressure, it better evaluate to pressure units.

The book was Elementary Fluid Mechanics, 4th Ed, John K. Vennard, 
John Wiley  Sons, copyright 1961.  An oldie but goodie, it might be 
available on abbooks.  In my opinion, the current books are stuffed 
with glitter and pabulum.

  That means the initial velocity must be 44m/s to arrive at the
  plate at 40m/s (90mph).

 mlb.com has a gameday display that shows data about each pitch, I
 think that's about the right amount of drag.  It also shows data
 about the arc of the ball and whatnot.

Glad to hear that I was close!

As far as getting people interested in science or engineering, most 
of the good engineers in my generation started out from an early age 
wanting to build something.   I wanted ham radio gear that I couldn't 
afford.  We knew (after trying) that the formal education was necessary 
to succeed.  So we entered are studies determined to get knowledge from 
them; good marks were secondary.

Perhaps our society has been wealthy for too many generations.  Few 
young people seem think about what they want to accomplish in life.  
Everything they could want is there - or so it might appear.

Oh, well.  Maybe they are right, and the era of nuts-and-bolts 
engineering and physical science are mostly over.  Sort of like the era 
of the great classical symphony composers.

Jim Kuzdrall
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Re: [OT] Simple math considered physics

2007-11-22 Thread Drew Van Zandt
I'm sure you can't MAKE kids interested in engineering, but there are
certainly classes of toys that a great many of the more geek-inclined people
I know remember fondly.

LEGO
Erector sets
Tinkertoys
Lincoln Logs
Piles of junk + imagination

Any I've missed?  If I ever have children they're definitely going to have
easy access LEGO and random electronic components.

(Books too, of course, but like many a young child that goes without
saying.)

--DTVZ
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Re: [OT] Simple math considered physics; turns out it's fun, not harmful

2007-11-21 Thread Bill Ricker
 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]
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Re: [OT] Simple math considered physics; turns out it's fun, not harmful

2007-11-21 Thread Ben Scott
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
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Re: [OT] Simple math considered physics; turns out it's fun, not harmful

2007-11-21 Thread Jim Kuzdrall
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
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Re: [OT] Simple math considered physics; turns out it's fun, not harmful

2007-11-21 Thread Greg Rundlett
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.  jokingMaybe the
space-time warp created by the massive concrete floor has an effect
compared to the relatively light sod at Fenway/joking

small attempt to bring subject on-topicI bet there is a lot going on
in Free Software to help physical scientists and mathematicians solve
complex problems/satbsot

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  :-)
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Re: [OT] Simple math considered physics; turns out it's fun, not harmful

2007-11-21 Thread Brian Chabot


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.)

 small attempt to bring subject on-topicI bet there is a lot going on
 in Free Software to help physical scientists and mathematicians solve
 complex problems/satbsot

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
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