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Jacked-up
59 Posts |
 Posted - 02/07/2010 : 16:31:23
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Does someone know the formula to determine the speed of a ball thrown compared to a professional?
To clarify - I have a pitching machine. It is set at 35MPH, 8 feet away from plate. What speed is this equivalent to from 60 ft 6 in ?
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TAZ980002
831 Posts |
Posted - 02/07/2010 : 20:09:59
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At 35mph an object travels 51.3 feet per second ((35*5280)/60/60). Divide the distance traveled by the speed per foot and you will have your reaction time - 8/51.3=.155 seconds
At 100mph an object travels 146.6 feet per second ((100*5280)/60/60). Divide the MLB distance by 146.6 and you have the reaction time for a 100mph fastball at the MLB level - 60.5/146.6=.413 seconds.
You might want to move the machine back a little !! |
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baseballpapa
1520 Posts |
Posted - 02/08/2010 : 08:14:05
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| Papa failed math in high school and the calculations furnished by Bandit 13 has got my head reeling. Papa is old school and if they are not hitting the ball where you have set the machine up then you should move the machine to a spot where they are hitting. |
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itsaboutbb
164 Posts |
Posted - 02/08/2010 : 09:54:55
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quote:
Originally posted by Bandit13
At 35mph an object travels 51.3 feet per second ((35*5280)/60/60). Divide the distance traveled by the speed per foot and you will have your reaction time - 8/51.3=.155 seconds
At 100mph an object travels 146.6 feet per second ((100*5280)/60/60). Divide the MLB distance by 146.6 and you have the reaction time for a 100mph fastball at the MLB level - 60.5/146.6=.413 seconds.
You might want to move the machine back a little !!
So he needs to move it back to about 21.18 feet to see reaction time of a MLB 100mph fast ball, right? |
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gabandit
25 Posts |
Posted - 02/08/2010 : 11:01:42
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An old rule of thumb when using pitching machines is to add 8-10 mph to the setting to represent "realized" speed. I.e. if you set your machine at your game distance, and good pitchers throw at let's say 65 mph, then set your machine at 55-58 mph. The reason is with a pitching machine there is no timing mechanism for the hitter, no pitcher in a stretch, windup, arm motion, etc.
Personally, I never used a machine to replicate game speed. I used it slower to work on mechanics. The advantage of a machine is consistency of location and not wearing out my arm!
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Jacked-up
59 Posts |
Posted - 02/08/2010 : 12:34:59
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It is a wiffle ball machine and limited room in basement...I am going to radar the speed to confirm and measure the distance to confirm it as well.
The distance is 14 ft. Good news is that my son can now hit it!!!...Now have to gun the speed... |
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TAZ980002
831 Posts |
Posted - 02/08/2010 : 12:48:46
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quote:
Originally posted by itsaboutbb
quote:
Originally posted by Bandit13
At 35mph an object travels 51.3 feet per second ((35*5280)/60/60). Divide the distance traveled by the speed per foot and you will have your reaction time - 8/51.3=.155 seconds
At 100mph an object travels 146.6 feet per second ((100*5280)/60/60). Divide the MLB distance by 146.6 and you have the reaction time for a 100mph fastball at the MLB level - 60.5/146.6=.413 seconds.
You might want to move the machine back a little !!
So he needs to move it back to about 21.18 feet to see reaction time of a MLB 100mph fast ball, right?
I'll take your word for it itsaboutbb. My wife looked at me like I was crazy when I was doing the math last night. |
Edited by - TAZ980002 on 02/08/2010 13:25:39 |
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bmoser
1633 Posts |
Posted - 02/08/2010 : 18:19:36
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| By how fast its going |
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whits23
596 Posts |
Posted - 02/08/2010 : 20:44:11
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| another rule of thumb is subtract 8mph from what any kid's dad tells you he throws |
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3sondad
220 Posts |
Posted - 02/09/2010 : 00:32:02
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Bandit ... You can get a headache trying to convert to feet/sec from MPH to figure out how fast you need to throw at different distances. I always try to keep math simple. I learned in Calculus class a long time ago that with math there is usually a quicker route to the same answer.
Here is a formula that might help around the park where you could use a calculator or your smart phone and not have to have access to conversion tables.
x MPH divided by a Feet EQUALS y MPH divided by b Feet
or y MPH = x MPH/ a Feet * b Feet.
Here are some examples...
80 MPH divided by 50 feet multiplied by 60.5 feet equals 98.64 MPH
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80 MPH/50'*60.5'= 98.64MPH
If you know 3 of the 4 you can ALWAYS solve the equation for the 4th. Don't get me wrong I know each side of the equation is not defined by itself in our example, because MPH/FT does not mean anything. What is important is the ratios on each side of the equation are equal and this simple calculation will work. It is a heck of a lot easier than converting MPH to Ft/sec just to convert it back to MPH.
More quick calculations:
100/60.5*50= 82.64 MPH (rounded)
100/60.5*46= 76.03 MPH (rounded)
100/60.5*54= 89.25 MPH (rounded)
Just to check my calculations were correct, I converted feet per second from MPH by looking up the conversion:
1st step - Convert 100 MPH to 146.76 feet per second
2nd step - 60.5 ft divided by 146.67 ft/second = 0.41249063 seconds
3rd step - 50.0 ft divided by 0.41249063 seconds = 121.214879 ft/seconds
4th step - Convert 121.214879 ft/second to 82.646506 MPH
So throwing a baseball at 82.64 MPH at 50' is equivalent to 100 MPH at 60'6", no matter if you convert it to ft/sec or use the simple formula above. Well my formula actually gets you to within 0.00X of a MPH of the true answer. ;-) |
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TAZ980002
831 Posts |
Posted - 02/09/2010 : 09:21:46
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3sondad, this is great !! So in Jacked-up's initial example the machine at 8' throwing 35mph is the equivalent of a 264mph fastball from 60.5 feet, right ??
35/8*60.5=264.68
BTW, I wondered what that headache was from the other night !! |
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Alter-Ego
802 Posts |
Posted - 02/09/2010 : 10:22:34
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| Anyone want to do the math at what swing speed you need to move a bat ~3' (initial location of the bat barrel to impact point) in order to be able to hit a 35mph pitch from 8'? |
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3sondad
220 Posts |
Posted - 02/09/2010 : 11:33:09
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quote:
Originally posted by Alter-Ego
Anyone want to do the math at what swing speed you need to move a bat ~3' (initial location of the bat barrel to impact point) in order to be able to hit a 35mph pitch from 8'?
I figured you could have easily pull that one out of your Home Depot handbook. I think it is in part of the Appendix AA page 2 or 3. I figure for a 10 year old kid to hit that pitch, he would have to start his swing as his dad is picking up the ball.
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Jacked-up
59 Posts |
Posted - 02/09/2010 : 18:41:55
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| The distance is 14 ft and the speed averaged 35mphs per the Bushnell radar gun. He hits more than he misses...He improved once he choked up on his 31/19 bat. A few more sessions and I will introduce the curve/sliders....hehehhehehhehe |
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Topic |
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How do you determine the speed of pitch
