If you are traveling at 100 MPH and have a gun that shoots bullets at 100 MPH

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brandonbull

Diamond Member
May 3, 2005
6,365
1,223
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Originally posted by: animalia
Originally posted by: MercenaryForHire
Those are some slow-ass bullets.

- M4H

wait so if a major league baseball pitcher throws a baseball out that same car...it's not gonna leave the car? wtf

If he tried to throw it in the same direction as the car it will be slower than the car.

 

mooncancook

Platinum Member
May 28, 2003
2,874
50
91
So if I'm traveling on a train at 100mph, and I throw a rock backward at 10mph, the rock is going to come back and hit me at 90mph. I'll be damned.
 

randay

Lifer
May 30, 2006
11,018
216
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Originally posted by: bigrash
Originally posted by: animalia
Originally posted by: MercenaryForHire
Those are some slow-ass bullets.

- M4H

wait so if a major league baseball pitcher throws a baseball out that same car...it's not gonna leave the car? wtf

is the pitcher standing on a mound on top of the car?

Does he pitch for the mets?
 

Tom

Lifer
Oct 9, 1999
13,293
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Originally posted by: JulesMaximus
Bullets travel much faster than 100mph.

some bullets travel a lot slower than 100mph. Ever shoot a Nerf gun ?

 

SViper

Senior member
Feb 17, 2005
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Originally posted by: mooncancook
So if I'm traveling on a train at 100mph, and I throw a rock backward at 10mph, the rock is going to come back and hit me at 90mph. I'll be damned.

ROFLMAO!!! That was a good one.
 

Evadman

Administrator Emeritus<br>Elite Member
Feb 18, 2001
30,990
5
81
Originally posted by: mooncancook
So if I'm traveling on a train at 100mph, and I throw a rock backward at 10mph, the rock is going to come back and hit me at 90mph. I'll be damned.

WTF? no. Pay attention. You are on the train. If you are on the train and throw something at 10 MPH in either direction (forward or back) , it will travel at 10 MPH away from you.

However if someone has a radar gun on the train platform, and somehow the radar gun could pick up the rock through the train, then the speed of the rock would be 90 and 110 respectively.
 

Kelvrick

Lifer
Feb 14, 2001
18,422
5
81
Originally posted by: SViper
Originally posted by: mooncancook
So if I'm traveling on a train at 100mph, and I throw a rock backward at 10mph, the rock is going to come back and hit me at 90mph. I'll be damned.

ROFLMAO!!! That was a good one.

I dont know if thats a joke, you're stupid or wahtever, but I had to laugh at that one. Good thing nobody poked their head in to wonder why I'm having fun working.
 

DT4K

Diamond Member
Jan 21, 2002
6,944
3
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Originally posted by: mooncancook
So if I'm traveling on a train at 100mph, and I throw a rock backward at 10mph, the rock is going to come back and hit me at 90mph. I'll be damned.

I can't tell if some of you are being sarcastic or are just dumb.
 

DT4K

Diamond Member
Jan 21, 2002
6,944
3
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Originally posted by: Aikouka
No, it wouldn't.

1) There's a wake that occurs (hence why Nascar people use Drafting to increase their speeds) when you drive that would at least throw the bullet even if it did stop in mid-air :p.

2) Once the bullet is fired from the "stationary" object (i.e. gun), the velocity of the stationary object shouldn't apply, therefore there is no "canceling" like you're trying to suggest.

EDIT: To elaborate on "stationary", I don't mean the object doesn't move at all. I meant it's stationary on the moving vehicle as in the gun is counted as moving at 100mph along with the truck.

1 is a valid point. Some of the air directly behind the vehicle will be getting pulled along with the vehicle. So in reality, it would probably move forward (relative to the ground) a little bit.
2 doesn't make any sense. Yes, once the bullet is fired, the gun is irrelevant. But that's not the point. If the gun has a muzzle velocity of 100 mph and it's moving backwards at 100mph (relative to the ground), then the bullet is going to exit the gun moving at 0 mph (relative to the ground) and will indeed fall to the ground (excluding the wind effects mentioned previously)
 

dxkj

Lifer
Feb 17, 2001
11,772
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Originally posted by: DVad3r
I would say yes? It would be like firing a gun backwards from a fighter jet traveling mach 2 or 3? Which leads me to another question, how do those machine gun canons on fighter jets still exceed velocity and hit stuff in front of them at high speeds?

lol, the casing they are fired out are already moving at the speed of the plane, so they shoot at plane speed + bullet speed.
 

Kirby

Lifer
Apr 10, 2006
12,028
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Originally posted by: Chiropteran
Originally posted by: nkgreen
But if you going forward at the speed of light and shoot a bullet forward at the speed what happens then? Riddle me that!!

You can not move forward "at the speed of light".

If you are moving forward at say, 90% the speed of light, and fire a a laser (which "shoots" at the speed of light), the laser would appear from your perspective to travel away from you at the speed of light.

However, someone who is at rest relative to you would see the laser as moving away from them at only the speed of light, not 190% the speed of light.

This isn't a paradox because of the way time and lengths are altered by the relative speeds. The distance you see the laser travel relative to yourself over a given time is greater than the distance the observer at rest sees the laser travel relative to you.

Ok :p

<---Takes physics next semester

 

amicold

Platinum Member
Feb 7, 2005
2,656
1
81
Originally posted by: nkgreen
But if you going forward at the speed of light and shoot a bullet forward at the speed what happens then? Riddle me that!!

If speeds are exact, I'd say the bullet wouldn't move from where it's charge ignited.

Edit:

Wait....wouldn't the speeds just add and stack since the point from where it's fired is moving at the speed of light already? Yes.
 

randay

Lifer
May 30, 2006
11,018
216
106
Originally posted by: SViper
Originally posted by: mooncancook
So if I'm traveling on a train at 100mph, and I throw a rock backward at 10mph, the rock is going to come back and hit me at 90mph. I'll be damned.

ROFLMAO!!! That was a good one.

Actually it will come back and hit you at 100mph.
 

ryan256

Platinum Member
Jul 22, 2005
2,514
0
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Yes the bullet drops to the ground.
Think of it like this. Since you're traveling at the bullet's muzzle velocity it behaves more like you are shooting the gun off of the bullet instead of the bullet out of the gun.
 

ebaycj

Diamond Member
Mar 9, 2002
5,418
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Originally posted by: nkgreen
But if you going forward at the speed of light and shoot a bullet forward at the speed what happens then? Riddle me that!!


The universe implodes in on itself, then explodes violently in a second Big Bang creating an all-new universe.
 

ebaycj

Diamond Member
Mar 9, 2002
5,418
0
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Originally posted by: DVad3r
Originally posted by: MercenaryForHire
Originally posted by: DVad3r
I would say yes? It would be like firing a gun backwards from a fighter jet traveling mach 2 or 3? Which leads me to another question, how do those machine gun canons on fighter jets still exceed velocity and hit stuff in front of them at high speeds?

http://en.wikipedia.org/wiki/Inertia :p

- M4H

Im fat lazy and slow, so let's say the plane is going mach 2 and the bullet get's shot out at mach 2 then it's speed is mach 4?

Indeed. (That is until it starts slowing down significantly due to air friction).

 

Doboji

Diamond Member
May 18, 2001
7,912
0
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I think it would still move from the spot you fired it at 100mph... the distance between you and the bullet would be increasing at 200mph