Air Trajectory B/C

Locked
Phys1cs
Member
Member
Posts: 129
Joined: November 10th, 2013, 6:53 pm
Division: Grad
State: MD
Has thanked: 0
Been thanked: 0

Re: Air Trajectory B/C

Post by Phys1cs »

windu34 wrote:Ya ping pong balls are the way to go if you want consistency

Be wary at first of ping pong balls, though. They're super light, so if they spin too much when launched, you can see them spin left/right on some of the farther shots.
User avatar
windu34
Staff Emeritus
Staff Emeritus
Posts: 1384
Joined: April 19th, 2015, 6:37 pm
Division: Grad
State: FL
Has thanked: 2 times
Been thanked: 42 times

Re: Air Trajectory B/C

Post by windu34 »

Phys1cs wrote:
windu34 wrote:Ya ping pong balls are the way to go if you want consistency

Be wary at first of ping pong balls, though. They're super light, so if they spin too much when launched, you can see them spin left/right on some of the farther shots.
Yeah you need to comne up with a very consistent device as far as air flow/movement if you want to do well with ping pong balls. Small bursts of uneven air will cause alot of problems
Boca Raton Community High School Alumni
University of Florida Science Olympiad Co-Founder
Florida Science Olympiad Board of Directors
[email protected] || windu34's Userpage
sciolylover13
Member
Member
Posts: 95
Joined: June 5th, 2015, 10:23 am
Division: B
State: AL
Has thanked: 0
Been thanked: 0

Re: Air Trajectory B/C

Post by sciolylover13 »

windu34 wrote:
Phys1cs wrote:
windu34 wrote:Ya ping pong balls are the way to go if you want consistency

Be wary at first of ping pong balls, though. They're super light, so if they spin too much when launched, you can see them spin left/right on some of the farther shots.
Yeah you need to comne up with a very consistent device as far as air flow/movement if you want to do well with ping pong balls. Small bursts of uneven air will cause alot of problems
So far our device has been pretty consistent with a variation of 2-3 cm using ping pong balls. Of course for Nats 2-3 cm is 2-3 cm too much, so I'm working on making it more consistent.
2015-2016 events:Chattahoochee/Dodgen/Regionals/State/Nats?
Anatomy and Physiology: 4/////
Green Generation: 6/////
Air Trajectory: NA/////
Crime Busters: 2/////
User avatar
bernard
Administrator
Administrator
Posts: 2499
Joined: January 5th, 2014, 3:12 pm
Division: Grad
State: WA
Pronouns: He/Him/His
Has thanked: 186 times
Been thanked: 795 times
Contact:

Re: Air Trajectory B/C

Post by bernard »

sciolylover13 wrote:
bernard wrote: And a related question: what do you do when you can't find a ball that fits your pipe perfectly (but of course your pipe is larger than your ball)? Last season we used tape, but noticed over time it lost consistently. Started with great consistency, but over time it would somehow act weirdly (making the projectile fit very, very tightly) so not so great consistency in the long run, at least from our experience.
What ball are you using? I use plastic ping pong balls that fit a 1 1/4* in. PVC pipe perfectly.

*I bought said PVC pipe last year, so I don't remember the exact diameter of it. I'm pretty sure it was 1 1/4 though.
Was a competitor last year--we used Joola orange ping pong balls off Amazon with 1.5" PVC (and I'm pretty sure you had 1.5" PVC as that's the approximate diameter of regulation table tennis balls). It fit nicely, but was not tight enough.
"One of the ways that I believe people express their appreciation to the rest of humanity is to make something wonderful and put it out there." – Steve Jobs
sciolylover13
Member
Member
Posts: 95
Joined: June 5th, 2015, 10:23 am
Division: B
State: AL
Has thanked: 0
Been thanked: 0

Re: Air Trajectory B/C

Post by sciolylover13 »

bernard wrote:
sciolylover13 wrote:
bernard wrote: And a related question: what do you do when you can't find a ball that fits your pipe perfectly (but of course your pipe is larger than your ball)? Last season we used tape, but noticed over time it lost consistently. Started with great consistency, but over time it would somehow act weirdly (making the projectile fit very, very tightly) so not so great consistency in the long run, at least from our experience.
What ball are you using? I use plastic ping pong balls that fit a 1 1/4* in. PVC pipe perfectly.

*I bought said PVC pipe last year, so I don't remember the exact diameter of it. I'm pretty sure it was 1 1/4 though.
Was a competitor last year--we used Joola orange ping pong balls off Amazon with 1.5" PVC (and I'm pretty sure you had 1.5" PVC as that's the approximate diameter of regulation table tennis balls). It fit nicely, but was not tight enough.
Yeah, I think it was 1.5''. I thought ours was a pretty good fit. We used white plastic ping pong balls from Academy. I don't remember the company.
2015-2016 events:Chattahoochee/Dodgen/Regionals/State/Nats?
Anatomy and Physiology: 4/////
Green Generation: 6/////
Air Trajectory: NA/////
Crime Busters: 2/////
Leznupar
Member
Member
Posts: 4
Joined: January 2nd, 2016, 8:41 pm
Division: C
State: NY
Has thanked: 0
Been thanked: 0

Re: Air Trajectory B/C

Post by Leznupar »

Hey, I know it's a bit late to ask for help, but Id like to know if the weight has to directly trigger the device? Im buying a spring-loaded toy gun to use to launch the ball, however, my weight would have to indirectly set off the trigger, almost like a chain effect. In addition, would the fact that the gun is spring-loaded make it induced by air pressure? I was thinking in my head that the more compressed the spring is, the more air there is to "explode" once released. Although, the gun involves a bar hitting the ball, not the actual spring itself (which Im assuming is attached to the bar at the rear).
User avatar
windu34
Staff Emeritus
Staff Emeritus
Posts: 1384
Joined: April 19th, 2015, 6:37 pm
Division: Grad
State: FL
Has thanked: 2 times
Been thanked: 42 times

Re: Air Trajectory B/C

Post by windu34 »

Leznupar wrote:Hey, I know it's a bit late to ask for help, but Id like to know if the weight has to directly trigger the device? Im buying a spring-loaded toy gun to use to launch the ball, however, my weight would have to indirectly set off the trigger, almost like a chain effect. In addition, would the fact that the gun is spring-loaded make it induced by air pressure? I was thinking in my head that the more compressed the spring is, the more air there is to "explode" once released. Although, the gun involves a bar hitting the ball, not the actual spring itself (which Im assuming is attached to the bar at the rear).
READ THE RULES PLEASE!!!
You must convert gravitational potential energy into Air pressure which you use to launch a projectile.
So basically, NO SPRING
Boca Raton Community High School Alumni
University of Florida Science Olympiad Co-Founder
Florida Science Olympiad Board of Directors
[email protected] || windu34's Userpage
Leznupar
Member
Member
Posts: 4
Joined: January 2nd, 2016, 8:41 pm
Division: C
State: NY
Has thanked: 0
Been thanked: 0

Re: Air Trajectory B/C

Post by Leznupar »

I thought setting off a ball to hit the trigger was considered "gravitational potential energy", since it'll be going down an incline of some sort to actually hit the trigger?
User avatar
windu34
Staff Emeritus
Staff Emeritus
Posts: 1384
Joined: April 19th, 2015, 6:37 pm
Division: Grad
State: FL
Has thanked: 2 times
Been thanked: 42 times

Re: Air Trajectory B/C

Post by windu34 »

Leznupar wrote:I thought setting off a ball to hit the trigger was considered "gravitational potential energy", since it'll be going down an incline of some sort to actually hit the trigger?
No. You need actual air pressure to launch the ball either directly or indirectly. A spring does not qualify
Boca Raton Community High School Alumni
University of Florida Science Olympiad Co-Founder
Florida Science Olympiad Board of Directors
[email protected] || windu34's Userpage
User avatar
Fanglin
Member
Member
Posts: 116
Joined: November 22nd, 2015, 12:36 pm
Division: C
State: CA
Has thanked: 0
Been thanked: 0

Re: Air Trajectory B/C

Post by Fanglin »

sciolylover13 wrote:
bernard wrote: And a related question: what do you do when you can't find a ball that fits your pipe perfectly (but of course your pipe is larger than your ball)? Last season we used tape, but noticed over time it lost consistently. Started with great consistency, but over time it would somehow act weirdly (making the projectile fit very, very tightly) so not so great consistency in the long run, at least from our experience.
What ball are you using? I use plastic ping pong balls that fit a 1 1/4* in. PVC pipe perfectly.

*I bought said PVC pipe last year, so I don't remember the exact diameter of it. I'm pretty sure it was 1 1/4 though.
Even better, is a practice golf ball, which is very similar to a ping pong ball, but since it has dimples, it has less of a tendency to drift away from the desired trajectory.
Problems are better pursued with General Electric GE90-115 engines.

2016 Nats:
Road Scholar:4th 8-)
Bottle Rockets: 9th
Meteorology: 11th
Gliders: 21st

(other events: Green Gen, Crime Busters, Helicopters, Hovercraft, Air trajectory)

Former Cheesehead
Locked

Return to “Air Trajectory B/C”

Who is online

Users browsing this forum: No registered users and 1 guest