Super Soaker Central forums

Ben · 09-25-2003, 04:38 PM

WARNING: Full understanding of this topic requires at least knowledge of Algebra.
MATH ALERT!

I was messing with my 2L homemade again yesterday. I range tested it, and measured with a tape measure for maximum accuracy. It got 43 feet, which is really good for a XP type soaker. I then tested for shot time. It got about 24 seconds, which started to make me think. Only about half that shot past 20 feet. I did the calculations to get output, and it got really pathetic. That was because the drop-off rate in a XP soaker is almost linear. I remember that from the Aqua-NeXuS, back when I was a inexperienced user here. I wanted to see my drop-off rate in a equation, for both output and range. I then output tested it first for 10 seconds, and then for 20 seconds. 10 got 85 ml's a second and 20 got 62.5 ml's a second. Now, those numbers actually are the numbers for 5 seconds into the shot and 10 seconds into the shot, because when you think about it, it is the average output over a period of time. I then took out my trusty TI83+, and used it's LinReg(ax+B) function to find out the drop off rate for the output. LinReg(ax+B) looks at some lists of numbers I entered and turns them into an equation. It spat out y= -4.5x+107.5, where y is the output and x is the time into the shot. 107.5 is the maximum output this soaker can produce, the output once I pull the trigger. Lets call the max output mo for short. I then thought that the range equation should be similar, so I divided 107.5 by 43, the maximum range this soaker can put out, and I got exactly 2.5. Let's call the max range mr for shot. So in this soaker, and maybe all XPs, 2.5mr=mo. I then used this new knowledge to make an equation for the range drop-off, y= -1.8x+43. I think that you are seeing a trend here. I'll explain this:
*max refers to the stat once the trigger is pulled*
mo=max output
mr=max range
odr=output drop rate
rdr=range drop rate
To find the output of a XP soaker, use the equation y= -(odr)+mo
To find the range of a XP soaker, use the equation y= -(rdr)+mr
After than I wanted to find out the full shot time(until no water comes out) exactly. Let's call this fst. I did the math and when output and range = 0, time = 23.89 seconds. Isn't this fun?
I couldn't stop the soaker math. I wanted to find out how the output was in X. So, I looked around and found a bottle. It said that 473 ml = 16 oz. I knew that 1 oz is the output of a XP 70, what X is based off of, so I did a little math. The maximum X of this soaker is 3.6X, and when the output was 85ml's a second, it was 2.9X. So, this soaker has about a 3X nozzle? That's what I guesed when I made it, and it looks like I was right.
I started thinking about how all this info could help soaker mods and homemades. So I figured out the psi in my soaker. I knew that ther was 2L of air when empty in it, and I already measured in the past that the capacity of the soaker was 1.6L exaclty. So I did some more math. The 2L of air was compressed to the size of 400ml of air. So the pressure in there was 5 atmospheres. I did a quick google search and found out that 1 atmosphere = 14.6 psi. So I did 5*14.6 and got 73 psi. I then used that useful LinReg funtion again, knowing that the pressure at second 0 was 73 psi, and at 23.89 it was 14.6(1 atmosphere), and I got the equation y = -2.445x+73 to solve for the psi at any second in the shot. I then looked at the table funtion of my TI83+ and I saw that at 109.67 psi, the range should be 70 feet, and the output would be 175ml's a second. I know that the range won't be 70 feet due to stream breakup, and I also know that that output is only about 6X, but that really is amazing for a XP type soaker, and it is 100% possible. Maybe through better nozzles and rifling this could be achieved...

So what do you guys think about this almost article I posted? I think I'll post it at WWN.

Neuro · 09-25-2003, 08:07 PM

I REALLY need a graphing calculator. :P

Ben · 09-26-2003, 05:01 AM

I posted this at WWN, too. It seems to have been more successful there.

Neuro · 09-26-2003, 10:22 AM

boo! I can't get into wwn because they never sent me the activation email and theres no re-send link.

toothpickmatt · 10-01-2003, 05:11 PM

interesting interesting....
thats cool that ya actualy went about figuring out all the math for that. algabraII trig class applyed to the real world =P cool cool my only question is how close to a line is the drop off curve? cause I know for an XP gun that it starts off pritty linerar.... but then as it progresses down it takes forever to approch 0... so im not really sure how you swould define that... but yeah workign with a line is cool for how accurite we need to be
good job
=D

Ben · 10-01-2003, 06:04 PM

The full shot time is how long the shot will last to get 0 range and 0 output. I think thats what you meant. I think that the output and range drop is directly related to the pressure drop, and I'm guessing that the pressure drops linearly.

Neuro · 10-03-2003, 10:14 PM

hey! it didn't go over my head! I'm impressed with my algebra teacher.

09-25-2003, 04:38 PM	#1
Ben Founder Join Date: Mar 2003 Location: College Park, Maryland Posts: 6,016 UserID: 1	WARNING: Full understanding of this topic requires at least knowledge of Algebra. MATH ALERT! I was messing with my 2L homemade again yesterday. I range tested it, and measured with a tape measure for maximum accuracy. It got 43 feet, which is really good for a XP type soaker. I then tested for shot time. It got about 24 seconds, which started to make me think. Only about half that shot past 20 feet. I did the calculations to get output, and it got really pathetic. That was because the drop-off rate in a XP soaker is almost linear. I remember that from the Aqua-NeXuS, back when I was a inexperienced user here. I wanted to see my drop-off rate in a equation, for both output and range. I then output tested it first for 10 seconds, and then for 20 seconds. 10 got 85 ml's a second and 20 got 62.5 ml's a second. Now, those numbers actually are the numbers for 5 seconds into the shot and 10 seconds into the shot, because when you think about it, it is the average output over a period of time. I then took out my trusty TI83+, and used it's LinReg(ax+B) function to find out the drop off rate for the output. LinReg(ax+B) looks at some lists of numbers I entered and turns them into an equation. It spat out y= -4.5x+107.5, where y is the output and x is the time into the shot. 107.5 is the maximum output this soaker can produce, the output once I pull the trigger. Lets call the max output mo for short. I then thought that the range equation should be similar, so I divided 107.5 by 43, the maximum range this soaker can put out, and I got exactly 2.5. Let's call the max range mr for shot. So in this soaker, and maybe all XPs, 2.5mr=mo. I then used this new knowledge to make an equation for the range drop-off, y= -1.8x+43. I think that you are seeing a trend here. I'll explain this: max refers to the stat once the trigger is pulled mo=max output mr=max range odr=output drop rate rdr=range drop rate To find the output of a XP soaker, use the equation y= -(odr)+mo To find the range of a XP soaker, use the equation y= -(rdr)+mr After than I wanted to find out the full shot time(until no water comes out) exactly. Let's call this fst. I did the math and when output and range = 0, time = 23.89 seconds. Isn't this fun? I couldn't stop the soaker math. I wanted to find out how the output was in X. So, I looked around and found a bottle. It said that 473 ml = 16 oz. I knew that 1 oz is the output of a XP 70, what X is based off of, so I did a little math. The maximum X of this soaker is 3.6X, and when the output was 85ml's a second, it was 2.9X. So, this soaker has about a 3X nozzle? That's what I guesed when I made it, and it looks like I was right. I started thinking about how all this info could help soaker mods and homemades. So I figured out the psi in my soaker. I knew that ther was 2L of air when empty in it, and I already measured in the past that the capacity of the soaker was 1.6L exaclty. So I did some more math. The 2L of air was compressed to the size of 400ml of air. So the pressure in there was 5 atmospheres. I did a quick google search and found out that 1 atmosphere = 14.6 psi. So I did 514.6 and got 73 psi. I then used that useful LinReg funtion again, knowing that the pressure at second 0 was 73 psi, and at 23.89 it was 14.6(1 atmosphere), and I got the equation y = -2.445x+73 to solve for the psi at any second in the shot. I then looked at the table funtion of my TI83+ and I saw that at 109.67 psi, the range should be 70 feet, and the output would be 175ml's a second. I know that the range won't be 70 feet due to stream breakup, and I also know that that output is only about 6X, but that really is amazing for a XP type soaker, and it is 100% possible. Maybe through better nozzles and rifling this could be achieved... So what do you guys think about this almost article I posted? I think I'll post it at WWN. __________________ Note: I am busy so if I am slow to respond, be patient.* email: ben at sscentral dot org / Forum rules / Read this page before emailing me. Do not send me a PM or email with a water gun question if someone else could answer the question. Post at the forums. You will get a response from me along with others' views or ideas. Do not send me a PM or email about reading a certain post unless it's been a few days since you've posted. I try to read every post but do miss some.

09-25-2003, 08:07 PM	#2
Neuro Retired Moderator Join Date: May 2003 Location: Michigan Posts: 1,081 UserID: 30	I REALLY need a graphing calculator. :P __________________ "I used to care, but now I take a pill for that." You can pretty much ignore the times on that, I rarely ever have Xfire on when I play. I should, though.

09-26-2003, 05:01 AM	#3
Ben Founder Join Date: Mar 2003 Location: College Park, Maryland Posts: 6,016 UserID: 1	I posted this at WWN, too. It seems to have been more successful there. __________________ Note: I am busy so if I am slow to respond, be patient. email: ben at sscentral dot org / Forum rules / Read this page before emailing me. Do not send me a PM or email with a water gun question if someone else could answer the question. Post at the forums. You will get a response from me along with others' views or ideas. Do not send me a PM or email about reading a certain post unless it's been a few days since you've posted. I try to read every post but do miss some.

09-26-2003, 10:22 AM	#4
Neuro Retired Moderator Join Date: May 2003 Location: Michigan Posts: 1,081 UserID: 30	boo! I can't get into wwn because they never sent me the activation email and theres no re-send link. __________________ "I used to care, but now I take a pill for that." You can pretty much ignore the times on that, I rarely ever have Xfire on when I play. I should, though.

10-01-2003, 06:04 PM	#6
Ben Founder Join Date: Mar 2003 Location: College Park, Maryland Posts: 6,016 UserID: 1	The full shot time is how long the shot will last to get 0 range and 0 output. I think thats what you meant. I think that the output and range drop is directly related to the pressure drop, and I'm guessing that the pressure drops linearly. __________________ Note: I am busy so if I am slow to respond, be patient. email: ben at sscentral dot org / Forum rules / Read this page before emailing me. Do not send me a PM or email with a water gun question if someone else could answer the question. Post at the forums. You will get a response from me along with others' views or ideas. Do not send me a PM or email about reading a certain post unless it's been a few days since you've posted. I try to read every post but do miss some.

10-01-2003, 05:11 PM	#5
toothpickmatt Senior Member Join Date: Mar 2003 Posts: 81 UserID: 12	interesting interesting.... thats cool that ya actualy went about figuring out all the math for that. algabraII trig class applyed to the real world =P cool cool my only question is how close to a line is the drop off curve? cause I know for an XP gun that it starts off pritty linerar.... but then as it progresses down it takes forever to approch 0... so im not really sure how you swould define that... but yeah workign with a line is cool for how accurite we need to be good job =D

10-03-2003, 10:14 PM	#7
Neuro Retired Moderator Join Date: May 2003 Location: Michigan Posts: 1,081 UserID: 30	hey! it didn't go over my head! I'm impressed with my algebra teacher. __________________ "I used to care, but now I take a pill for that." You can pretty much ignore the times on that, I rarely ever have Xfire on when I play. I should, though.

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