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Canadian GP
11-25-2002, 07:50 PM
After an afternoon of friendly bushball I was complaining that my Piranha was not getting a lot of distance even with a full tank. My bud pipes up and says all balls take the same amount of time to hit the ground. I start laughing...."you're saying 2 balls fired at the same time will hit the ground together, no matter what shoots them?"

He says if you drop a ball from a barrel it will hit the ground at the same time as one fired from any marker.

True or false?
Sinnet
11-25-2002, 07:56 PM
all shots fired at the same velocity at the same angle under the same conditions will hit the ground at the same time.


so, true
Sir Chopsalot
11-25-2002, 07:58 PM
yup
Canadian GP
11-25-2002, 07:58 PM
NO NO...he says a ball dropped from the front of a barrel(not shot)will hit the ground at the same time as a fired ball.
LittMag
11-25-2002, 08:01 PM
If only people paid attention during their physics classes.

If you fire a gun/marker/blowgun/dartgun/small child out of a cannon from a level parallel to the ground. And drop something the same size from the same level they will both hit the ground at the same time.

If that was to convoluted for you, then just accept that what your friend said was true. As long as the marker isn't angled upward or downward, the paint will fall at the same speed, and hit the ground at the same time.
shartley
11-25-2002, 08:10 PM
Originally posted by LittMag
If only people paid attention during their physics classes.

If you fire a gun/marker/blowgun/dartgun/small child out of a cannon from a level parallel to the ground. And drop something the same size from the same level they will both hit the ground at the same time.

If that was to convoluted for you, then just accept that what your friend said was true. As long as the marker isn't angled upward or downward, the paint will fall at the same speed, and hit the ground at the same time.
What? That is NOT true. LOL

If you DROP two objects of the same relative size and shape, but different weights, they will hit the ground at the same time. But if you FIRE one at the ground and drop another, they will NOT hit the ground at the same time. If the one fired is fired at a higher velocity than the object being dropped, it will reach the ground faster.

The dropped object takes time to reach maximum velocity, and is doing so from a dead stop. The object being fired is already moving at a substantial speed.....

Under YOUR way of thinking, if you also fire two guns at the ground, one firing a standard load 22, and the other firing a Magnum 45 load, they will both hit the ground at the same time too, or that a standard load 45 and a Magnum load 45 would do the same.... but this can't be farther from the truth.

I think you may want to go take those physics classes again. ;)

(ADDED: Before getting out the ropes and lynching me... keep reading this thread... I know many would LOVE to take a shot at SHARTLEY... but you missed your chance. ;) I am keeping these online to show you all I DO have a sense of humor. :D)
yeahthatsme
11-25-2002, 08:17 PM
i think he meant the gun would be shooting horizontal....
shartley
11-25-2002, 08:21 PM
Originally posted by yeahthatsme
i think he meant the gun would be shooting horizontal....
That still would not work.... What is the distances used? Velocities? etc.

His pals ideas are wrong.. period... sorry. ;)

(ADDED: Before getting out the ropes and lynching me... keep reading this thread... I know many would LOVE to take a shot at SHARTLEY... but you missed your chance. ;) HeeHee.. keep reading. :D)
petefol
11-25-2002, 08:23 PM
when they fall they both accelerate at -32 feet per sec per sec or -9.8 meters per sec per sec, even if one object is moving and the other is just falling, they still fall at the same rate.
LittMag
11-25-2002, 08:28 PM
Yes, I meant horizontal, I'm sorry about that.

Distance and Velocity have nothing to do with the acceleration of an object (regardless of weight) towards the ground. An objects horizontal speed has nothing to do with how quickly it falls.

This is all assuming that there are no effects of friction or other sources.
http://www.physicsclassroom.com/mmedia/newtlaws/efff.html
shartley
11-25-2002, 08:30 PM
Okay.. hold on….. after reading this again……

What is being said is that given equal conditions, an object dropped from 4 feet, will hit the ground at the same time as a similar object fired on an exact horizontal position being the same 4 feet off the ground, no matter what velocity it is fired at.

Interesting…

So, if you fire two markers, one set at 200fps, and the other at 300fps, both will hit the ground at the same time….. but the one set at higher fps will just go farther in that amount of time. Sounds reasonable….. This I will concede.

I misread what was being said…. Sorry.

Now in practicality, I will say it will never happen using paintballs, or anything else. Only on paper and in a perfect world would this work. How many times have we seen paintballs curve in the air, or rise/fall in strange ways? ;) There are simply too many variables to mess things up.

So, I guess you could say he was correct in principle and theory, but you should not put money on it actually working in practical application. ;)
AGD
11-25-2002, 08:30 PM
Saaaammmmmm,

Do you really know what your talking about here???? Just to confirm, you believe that if a ball is fired horizontally from a barrel it will take less time to hit the ground than a ball dropped from the same height? This is of course dissregarding all spin effects.

AGD
shartley
11-25-2002, 08:32 PM
Originally posted by AGD
Saaaammmmmm,

Do you really know what your talking about here???? Just to confirm, you believe that if a ball is fired horizontally from a barrel it will take less time to hit the ground than a ball dropped from the same height? This is of course dissregarding all spin effects.

AGD
LOL Sorry... too late Tom. ;) Read the post above yours. :D

(Plus you have to cut me some slack.... long day, much work, and major laptop problems... LOL)
agdemagman69
11-25-2002, 08:34 PM
lol, i remember a lecture last year where the same exact thing happened

everybody was like NO! that wont happen, and then my teacher made a demonstration with a dart gun and a dart, in the same format as littmags experiment


ITS TRUE!!
LittMag
11-25-2002, 08:43 PM
Shartley... you really had me runnin around for a bit there. I was surprised that you were the one questioning what I had said, but as long as we can all agree what should happen in an ideal world it's all good ;) I was scrambling to find the animation I saw earlier of a cannon firing a ball and someone dropping one at the same moment, but all I found was the elephant and feather.
shartley
11-25-2002, 08:46 PM
Originally posted by LittMag
Shartley... you really had me runnin around for a bit there. I was surprised that you were the one questioning what I had said, but as long as we can all agree what should happen in an ideal world it's all good ;) I was scrambling to find the animation I saw earlier of a cannon firing a ball and someone dropping one at the same moment, but all I found was the elephant and feather.
LOL Nah, I just read it wrong, and am VERY tired. As you can see, it did not take me much time to shake my head and say “What? I just missed something…. Let me read that again.” LOL

I am only leaving it online to show that I am not perfect, and never claimed to be…. but one such mistake in 2 years is a pretty good record. ;) I hope everyone enjoys it. :D
benzy2
11-25-2002, 08:51 PM
"But feeling sorry for your actions does not mean you should not pay the piper for dance."

You still were wrong:D

I just saw my one chance in life to pick on your mistake and had to take it. Its all in fun
sniper1rfa
11-25-2002, 08:54 PM
actually, shartley is right, sorta...

you forgot the curvature of the earth. hell, if it was going 18000 m/s/s (i think thats the number) it would hit in like taiwan (exaggeration) 30 minutes later... without friction it would never hit the ground...

;)
LittMag
11-25-2002, 08:55 PM
In case anyone still cares
http://hyperphysics.phy-astr.gsu.edu/hbase/traj.html#tra2
shartley
11-25-2002, 08:57 PM
Originally posted by benzy2
"But feeling sorry for your actions does not mean you should not pay the piper for dance."

You still were wrong:D

I just saw my one chance in life to pick on your mistake and had to take it. Its all in fun
HeeHee very true... but I corrected myself before others did. ;) :p

(But I guess we can call this an early Christmas Gift to AO. ;))
spazzed
11-25-2002, 08:59 PM
You wanna know about Gravity, eh? It's a good thing. Period. :D :cool:
shartley
11-25-2002, 09:05 PM
You want to know about gravity? YOU CAN’T TAKE THE GRAVITY!



:D
AllAmericanMag
11-25-2002, 09:10 PM
Brain.....hurts! Learning......too much!!! Must....turn on.....TV! :D
HoppysMag
11-25-2002, 09:17 PM
AAAAHHHHHHH im in conceptual physics and even i knew enough to bust samn on this AAAAHHHHH Darn me and my day off from AO! i wanted to prove sam wrong....:mad:
petefol
11-25-2002, 09:51 PM
hehe i was right
I AM SO SMART S-M-R-A-T!
Spray Painter
11-25-2002, 10:04 PM
if your so smart then how do you spell smart?
AGD
11-26-2002, 03:42 AM
LOL!! I almost caught him. We tied for the punch line!

AGD
shartley
11-26-2002, 08:15 AM
:D
ben_JD
11-26-2002, 10:59 AM
Isn't this interesting?

What effect does this conversation have on the "different markers, different range" debate? I think that the same folks who are convinced that objects with relative velocity will stay aloft longer than objects with no relative kinetic energy along a plane perpendicular to the force of gravity are the same folks who think that Autocockers/Matrices/[insert other marker name here] have longer range than other markers. That's what I really thought SHartley was going after.

[Edit: I initially had that last sentence grammatically correct, but it sounded so corny I reworded. Sometimes ending a sentence with a preposition is easier than confusing people.]
FatMan
11-26-2002, 11:27 AM
Said effects are strictly valid only in a vacuum. For practical purposes they are usually true with paintballs.

Personally, I think gravity is over-rated. I know *I* would be much better without it!

FatMan
Restola
11-26-2002, 12:48 PM
I stopped reading about halfway down, but what it comes down to is gravity doesnt stop working simply because an object is moving.

Otherwise my plane would weigh less and less the faster I went and I could "fly" off the earth :)
Tom Sparkman
11-26-2002, 12:58 PM
I remember doing an experient in physics 30 years ago...

Metal plate 5 feet off the ground held by an electromagnet. Blowgun boresighted on the plate (and leveled) with the wires from the e-magnet at the muzzle. When a steel ball was blown out the tube, the circuit would be broken and the plate would fall. The ball would always impact the steel plate, sometimes right above the ground.

That demonstration seemed to drive it home for me.

Tom
nippinout
11-26-2002, 01:26 PM
Isn't gravity merely our perception of what's really going on?

Mass bends time and space. The more dense an object is, the more it warps time and space.

An object falling towards the earth isn't this magical thing, but the masses acting on time and space.

Err... something like that. Anybody out there that really knows their physics? Not kinematics, but real physics. :)

My brain hurts.
Restola
11-26-2002, 03:10 PM
Gravity is what lets the beer flow from the can to my mouth.

College physics that really matter :)
Jason Reed
11-26-2002, 03:47 PM
hey dude you stole my sig,
i will kill you hehe
lol just kinding