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bugboy900
09-12-2006, 10:27 AM
if my friend was pitching to me at 65mph at 50feet away then in reality how fast would this simulate.

65mph at 50 feet =

GFK
09-12-2006, 01:03 PM
if my friend was pitching to me at 65mph at 50feet away then in reality how fast would this simulate.

65mph at 50 feet =

65 mph would be the real speed. The reaction time would be approximately equivalent to a 78.7 mph fastball from 60.5'. The thing is, a 65 mph fastball passes through the strike zone much slower than a 79 mph fastball. The reaction times would be nearly equal but the closing rate is entirely dependent on velocity. the higher closing rate, the greater the demand for better timing.

jbooth
09-12-2006, 01:40 PM
if my friend was pitching to me at 65mph at 50feet away then in reality how fast would this simulate.

65mph at 50 feet =

If you mean; how does 65mph at 50 feet, relate to a pitch from 60 feet 6 inches;

It is roughly the same as a pitch thrown at 78mph from a pro mound.

The math formula is;

divide 60.5 by the distance you actually throw from (50).

60.5/50 = 1.21

Now multiply your speed from 50 feet (65) by 1.21

65 * 1.21 = 78.65mph from 60.5 feet

If you throw 65 from 46 feet (Little League distance) 60.5/46 = 1.32

65 * 1.32 = 85.8

Girls softball 60.5 / 40 = 1.51 so 65 * 1.51 = 98.15

EdmondsFan#1
09-12-2006, 08:37 PM
Actually, i heard the ball approximetly slows down 1mph every 7 inches... or was it 7 feet... something like that.

jbooth
09-12-2006, 09:32 PM
Actually, i heard the ball approximetly slows down 1mph every 7 inches... or was it 7 feet... something like that.

It depends on how fast it is going when it leaves the hand. It begins to decelerate right after it leaves the hand. The faster it is going to start with, the smaller the deceleration rate.

A pitch that is going 98mph at release is going about 90mph at the plate. So, it loses 8mph over about 55 feet. So, that is about 1 mph for every 7 feet.

An 88mph pitch probably loses 9 mph. 1 mph for every 6 feet.

Little League pitches lose speed very quickly. A 62mph pitch loses 10mph over just 40 feet. A loss rate of 1 mph every 4 feet.

GFK
09-13-2006, 09:03 AM
It depends on how fast it is going when it leaves the hand. It begins to decelerate right after it leaves the hand. The faster it is going to start with, the smaller the deceleration rate.

A pitch that is going 98mph at release is going about 90mph at the plate. So, it loses 8mph over about 55 feet. So, that is about 1 mph for every 7 feet.

An 88mph pitch probably loses 9 mph. 1 mph for every 6 feet.

Little League pitches lose speed very quickly. A 62mph pitch loses 10mph over just 40 feet. A loss rate of 1 mph every 4 feet.

I wonder how much the deceleration rate depends on ball spin? Faster pitching would be spinning faster. My knowledge of fluid dynamics tells me greater spin would reduce drag. JJA, what do you think?

Jake Patterson
09-13-2006, 09:11 AM
I wonder how much the deceleration rate depends on ball spin? Faster pitching would be spinning faster. My knowledge of fluid dynamics tells me greater spin would reduce drag. JJA, what do you think?

It would be an interesting study to time a four-seam versus a two seam fastball.

jbooth
09-13-2006, 10:16 AM
I wonder how much the deceleration rate depends on ball spin? Faster pitching would be spinning faster. My knowledge of fluid dynamics tells me greater spin would reduce drag. JJA, what do you think?

Yes, spin is a factor, but how detailed do you want to get?! :crazy

GFK
09-13-2006, 02:00 PM
It would be an interesting study to time a four-seam versus a two seam fastball.

To my understanding, a four-seam is usually faster than a two-seam. This, to my understanding, has to do with what is known in fluid dynamics as a boundary layer problem. Even though the two pitches may have been released at equal arm speed and spin, the boundary layers will be different. The four-seam will pass through the air with less decelleration than the two-seam. The two-seam will have more movement due to the differences in the boundary layer.

http://www.exploratorium.edu/baseball/putting_2.html

Catchingcoach
09-13-2006, 07:07 PM
A little anecdotal data for the thread. My son's 4-seam runs 87-89, his 2-seam runs 82-85 and tails in on righties 4-6 inches. He has never thrown a 2-seam faster the 85.

Jake Patterson
09-13-2006, 07:59 PM
To my understanding, a four-seam is usually faster than a two-seam.

The article you provided would support the above. I would however, like to research it further. It implies that a perfectly smooth surface resists air flow more than an orb with raised rough service.... Doesn't seem to make sense.

jbooth
09-13-2006, 08:38 PM
The article you provided would support the above. I would however, like to research it further. It implies that a perfectly smooth surface resists air flow more than an orb with raised rough service.... Doesn't seem to make sense.

May not make sense, but it is true. That's why golf balls have dimples. A smooth ball doesn't fly as far as one with dimples.

Here is a link to some info you might want to read, that explains it;

http://carini.physics.indiana.edu/E105/texture.html

Jake Patterson
09-13-2006, 09:03 PM
May not make sense, but it is true. That's why golf balls have dimples. A smooth ball doesn't fly as far as one with dimples.

Here is a link to some info you might want to read, that explains it;

http://carini.physics.indiana.edu/E105/texture.html

Thanks Jim - the article helps.

GFK
09-14-2006, 08:34 AM
.... Doesn't seem to make sense.

Now Jake, do you really think I would pass off bad information to you:rolleyes:

Jake Patterson
09-14-2006, 09:25 AM
Now Jake, do you really think I would pass off bad information to you:rolleyes:

Reviewed with my Physicist father last evening - His scientific explination went something like this - "What's wrong with you! Everyone knows that textured balls reduces drag at low speeds. Why do you think there's dimples on a golf ball? So much to teach and so little time..."

Even at fifty a parent is a parent.

He did say that at high speeds things become different.

jbooth
09-14-2006, 09:28 AM
Reviewed with my Physicist father last evening - His scientific explination went something like this - "What's wrong with you! Everyone knows that textured balls reduces drag at low speeds. Why do you think there's dimples on a golf ball? So much to teach and so little time..."

Even at fifty a parent is a parent.

He did say that at high speeds things become different.

Did your Dad mention the "Magnus Effect?"

see below;
http://en.wikipedia.org/wiki/Magnus_effect

Chris O'Leary
09-14-2006, 09:33 AM
The article you provided would support the above. I would however, like to research it further. It implies that a perfectly smooth surface resists air flow more than an orb with raised rough service.... Doesn't seem to make sense.

It's completely counterintuitive.

A slightly rough sphere moves through the air faster than a smooth sphere because the seams energize the boundary layer which REDUCES the drag.

Golf balls have dimples for the same reason; they energize the boundary layer and reduce the drag.

GFK
09-14-2006, 10:09 AM
...He did say that at high speeds things become different.

Check w/ him but I think "things become different" at above the speed of sound (fluid / media specific). This kind of speed would be well beyond the range of a pitched / hit baseball.

Jake Patterson
09-14-2006, 11:56 AM
Check w/ him but I think "things become different" at above the speed of sound (fluid / media specific). This kind of speed would be well beyond the range of a pitched / hit baseball.

Agree - and I will.

$tinky
04-25-2013, 09:05 PM
I was trying to use the formula in this thread to help me with a question. We are in machine pitch league and the machine is set at 35mph at 39 feet. What formula would I use to figure out what would be equal to this speed from say 25 feet? or 15 feet. I like to use machine at different distances in bp and I want to keep it close to what they are used to.

johnlanza
04-26-2013, 07:06 AM
May not make sense, but it is true. That's why golf balls have dimples. A smooth ball doesn't fly as far as one with dimples.

Here is a link to some info you might want to read, that explains it;

http://carini.physics.indiana.edu/E105/texture.html
I learn something all the time from this forum. That's why I check it out daily...