OK armchair physicists, explain this....

Bullets do climb. Let's you have an apple on a stick exactly five feet off the ground, and you are some distance away with the barrel of a rifle five feet off the ground. The only way to hit the apple with the bullet is to aim the barrel upward. So, the bullet will fly skyward before passing the apogee of the arc and continue the downward path into the apple.
So, the bullet climbs in relation to the target, but not in relation to the longitudinal axis of the rifle barrel.
-Kframe
 
Bullets don't climb. Haven't you guys ever sighted in a rifle? You SET the sights to make the rifle perform as desired. The charts in ballistics manuals simply describe the apogee IF SIGHTED IN AT THE DESIGNATED DISTANCE. The sights have to be set below the bore so that the bullet will drop to the point the sight is set for. But the bullet drops in the first inch after leaving the barrel.

As to the original question, sounds like we're coming up with a lot of estimations for the one thing I remember that should be easy-how far will the bullets drop in the first second. Initial speed is zero, acceleration is 32fps/s, so after one second speed is 32 fps. Therefore average speed is 32+0/2=16 fps.

Translation, they will drop right on 16 ft in the first second (still ignoring wind resistance, btw.)

S4S, if you're figuring without wind resistance as well, then something fouled up on your figuring of drop at 3000 ft, as that drop would be 16 ft by above figuring, since 3000 ft at stated MV of 3000fps would be 1 second. If you were figuring in wind resistance/slowing bullet, then you are WAY beyond my capabilities and please forgive my intrusion!! 'Cuz your results look pretty good in that case, could be right.
 
The problem at the top of this string is meant to show the effect between projectiles in motion and gravity,not taking into consideration the coefficient of friction
of a horizontal force applied by the air.

delta vertical displacement is equal to
one half gravitational acceleration times
delta time squared. and

delta horizontal displacement is equal to the velocity of the object times delta time.

and delta vertical displacement is directly
proportional to delta horizontal displacement

therefore-vertical displacement is equal to one half gravitational acceleration times
horizontal displacement divided by the velocity of horizontal displacement squared.

As another note the rate at which objects fall depend on where you are on the face of the eart,your distance from the center of the earth. 9.8m/s squared is a general rule of thumb close enough for most needs.which by the way is 32.2 ft/s squared.
So the two bullets in question will hit the ground at the same time. Sorry it was so long
safe shooting guys

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Glock-Never leave home without it.
 
BOOKIE!!! You're ALL WRONG!!!

Buttered toast ALWAYS falls butter-side down.

What you will have is a very surprised cat with a bullet up his...!

:), Art
 
The rotation of a bullet does cause it to drift in the direction of the rotation. Right hand twist causes the bullet to drift to the right. It is a factor in long range shooting, but not very significant at shorter ranges.

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Better days to be,

Ed
 
Ed, I believe that drift occurs only while the bullet travels through air. Jack's original thought problem had no air. (Anybody remember the problem? It was so long ago.) If the drift occurs in a vaccuum, then we have some satellites that are going to need refueling pretty soon. :)
 
The response that referred to the Hornady manual which shows bullet drop with a rifle sighted in at 100 yards does not address this theoretical problem. The gun would have to be bore sighted, with the rifle barrel in the same horizontal plane as the target. The bullet does, in fact, always begin the drop, the instant that it leaves the barrel. The caliber and velocity of the bullets are irrelevant.

So, who's got access to a 100 yd. vacuum, anywho????

We must not have enough to do!! :)

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Shoot to kill; they'll stop when they're dead!
 
Ok, Ok, so answer this, if you fire a bullet from a Glock chambered in 40 S&W, will the pieces of the slide or the pieces from the barrel hit the ground first?

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The new guy.

"I'm totin, this pistol because my dang SKS won't fit in my holster"

[This message has been edited by Jimmie (edited November 29, 1999).]
 
Jimmie, I relent that remark... I'm not all that bright but the way I understand it they dont go boom unless you fire a lead bullet loaded to 10mm specs. in a 40 s&w. lol

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Glock-Never leave home without it.
 
Technically a bullet will climb if not for gravity. In theory, the air pressure at the underside of the bullet is slightly more dense than it is on the top (skyward). Therefore there will be a lift at velocity.
Now, of course this probably isn't measurable except in a lab, but in theory the speeding bullet would land micro seconds after the one that was dropped.
Does that matter? Not at all, but hey, if ya wanna be precise.

SameShot

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SameShot, Different day
 
You all know a piece of buttered toast always lands butter side down and a cat always lands on its feet.

What if you tape a piece of buttered toast butter side up to the back of a cat and drop them? I think we have a clear case of the worlds first and only perpetual motion machine. If we tied that buttered toast cat to a string it should continually spin around creating enough energy to give power to the entire world for the next millenium.
 
The last thing we need to do is continue wasting TFL's disk space on this buttered toast/cat thing. But, I'm going to anyway. :)

I had never heard that joke before, but if you think about it, I think you guys have it wrong. The cat's feet should be glued to buttered toast, buttered side down. If the toast was tied to the cat's back as you suggest, the cat can land on it's feet and the buttered toast doesn't have to do anything.
 
Aw Jeez, I haven’t laughed so much in a ‘coons age.
I just can’t resist puttin’ in my $.02s worth, though.
Noticed several references to bullet VELOCITIES here, as well as bullet WEIGHTS.
Niether have anything to do with the problem as presented. What you’re talking about is
two free falling objects that start their sojourn at the same time & fall the exact same distance. All the rest is unnecessary window dressing. The velocities only determines WHERE they come to rest, not WHEN. Weight has no bearing at all.
Don Black / Tn.

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Don B / Tn.
 
Don, you are generally correct that velocity and weight have no bearing on the problem exactly as presented. However, the bullet trajectory from a rifle (different animal from the problem presented) does depend on velocity, weight, and point of zero, so these factors are relevant TO THE EXTENT THAT contrasting the problem presented to a rifle bullet trajectory is useful/helpful in understanding the former, by way of comparison
 
In 1967 my Rockville, Maryland high school physics teacher demonstrated this by firing a large rubber bullet through a pipe with compressed air at a coffee can hanging from an electromagnet near the ceiling at the opposite end of the classroom. By flipping one switch he fired the gun and cut the power to the magnet. The bullet always hit the falling can. And yes, he explained that air resistance would be a factor over longer distances. This guy was a trip and had actually worked with von Braun on the U.S. missle program.
 
Jack 99:

You stated: "The dropped bullet I'm fine with, but will the fired bullet really drop 32 feet over 3000 ft? I find this a little hard to swallow. That's a little over 1/2 mile. I know that the 30-06 drops pretty fast after 600 yds or so, but that fast?"

With respect, I believe you have forgotten a critical factor. In your initial posting you indicated that there was zero air resistance. If drag equals zero, I guarantee the 30-06 round would go MUCH further than 600 yards in a second.

Therefore, while both the "dropped" and the "fired" bullet would drop ~32 feet in the first second of flight, the shot bullet would go many miles with zero drag.

Hope this helps to straighten out your "physics problem".

[This message has been edited by RWK (edited December 10, 1999).]
 
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