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Posted: 9/11/2010 5:45:18 PM EDT
In an internet discussion with someone right now that is insisting that a bullet, when striking a vest and trauma plate has the inertia to knock someone off their feet because they've seen it in video from Iraq.



Anyone got any good scientific proof to refute this?



Also, in the same argument, he is stating that a laser in the 4+ megajoules range would strike a target in space so explosively that it would shift a 50 ton spacecraft and reverberate through the vessel.  The 50 ton vessel is the one being struck.



Ok hive, how about it?  Good proof on the bullet and good science geeky stuff on the lazorz...



-V
Link Posted: 9/11/2010 5:48:17 PM EDT
[#1]
f= 1/2 (mv) squared
Link Posted: 9/11/2010 5:50:04 PM EDT
[#2]

Link Posted: 9/11/2010 5:50:23 PM EDT
[#3]
One of newton's laws says that every force has an equal an opposite force.

Therefore, in order for the round from a weapon to knock someone over, it would also knock whoever fired at them as well.
Link Posted: 9/11/2010 5:51:41 PM EDT
[#4]
Find the MythBusters episode where they tested this one.

ETA: Here it is.
Link Posted: 9/11/2010 5:52:41 PM EDT
[#5]





Holy crap, I actually OWN this video...



-V



 
Link Posted: 9/11/2010 5:55:09 PM EDT
[#6]
The guy is full of it. Check the old video "Deadly weapons :firearms & firepower", the guy from Second chance shoots the host in the chest with a .308 FAL at like 2 ft. and the host is standing on one leg when he gets shot in vest he's wearing, FROM POINT BLANK RANGE.

 The thing you guys are argueing over was discussed in the film too.... conclusion was that if bullet hit so hard as to knock down the target the shooter would be knocked down as well due to laws of physics.
Link Posted: 9/11/2010 5:57:23 PM EDT
[#7]
Quoted:
One of newton's laws says that every force has an equal an opposite force.

Therefore, in order for the round from a weapon to knock someone over, it would also knock whoever fired at them as well.


Im not sure this is correct (wouldnt the buffer, spring , operation have an effect?). I have seen some of the trauma left (with plates) and it is pretty substantial.

ETA: Also, at what speed is the bullet traveling at 4ft vs say 100yds.
Link Posted: 9/11/2010 6:00:36 PM EDT
[#8]
Shoot him in the chest...





...in the name of science!
Link Posted: 9/11/2010 6:01:31 PM EDT
[#9]
I'll bet a nickel that after being confronted with absolute proof, he STILL wont believe it!
Link Posted: 9/11/2010 6:01:35 PM EDT
[#10]



Quoted:



Quoted:

One of newton's laws says that every force has an equal an opposite force.



Therefore, in order for the round from a weapon to knock someone over, it would also knock whoever fired at them as well.




Im not sure this is correct (wouldnt the buffer, spring , operation have an effect?). I have seen some of the trauma left (with plates) and it is pretty substantial.



ETA: Also, at what speed is the bullet traveling at 4ft vs say 100yds.


It begins decelerating the moment it leaves the barrel.  The action of the gun will absorb some, but he is correct.  If a bullet is capable of knocking you off your feet through Kenetic Energy alone, it will also knock the the shooter off their feet....



 
Link Posted: 9/11/2010 6:03:55 PM EDT
[#11]
Anyone that says a bullet can "knock" someone over or down is not worth arguing with, but sadly I have seen my fair share of "professionals" also using the term. Maybe its me that's wrong.
Link Posted: 9/11/2010 6:04:23 PM EDT
[#12]
Also keep in mind the mass and balance of both shooter and target.  A well balanced heavy shooter might remain upright while a lighter and off balance target could fall over.

That happened to me when I was 6 years old and shooting my dad's 12ga shotgun.  As the shooter, it knocked me right over even though he never had a problem with it  
Link Posted: 9/11/2010 6:04:43 PM EDT
[#13]



Quoted:


Find the MythBusters episode where they tested this one.



ETA: Here it is.

Embedded for ya!















 
Link Posted: 9/11/2010 6:20:38 PM EDT
[#14]
Thanks for the vids guys, anyone got any super science thing on the laser?



-V
Link Posted: 9/11/2010 6:25:02 PM EDT
[#15]
'Knocking over' would be sort of a misnomer......might drop in tracks...maybe take 20 minutes to bleed out....but yes...could 'knock' someone over in their tracks...just maybe not the tracks they were in when hit.

Spacecraft burned by laser....well sheeet?...I imagine if you burn a hole in it...all the air rushes out...making a helluva noise...and would shift the spacecraft's flight-path/orbit.

Hell! He's 'right'!!!
Link Posted: 9/11/2010 6:28:17 PM EDT
[#16]
The impulse on the shooter and the impulse on the target are 2 different things.
Link Posted: 9/11/2010 6:43:12 PM EDT
[#17]
I've been "knocked off my feet" by a paintball. Actually, it was me jumping back in surprise from the hit. I suspect thats what they saw in the Iraq vid, some soldier taking a bullet in the trauma plate, and jumping back and down in surprise.
Link Posted: 9/11/2010 6:44:31 PM EDT
[#18]



Quoted:


The impulse on the shooter and the impulse on the target are 2 different things.


Force is force.



People fall over because they're surprised or a sudden loss of blood pressure. Not because of force.



 
Link Posted: 9/11/2010 6:44:58 PM EDT
[#19]
Quoted:
Anyone that says a bullet can "knock" someone over or down is not worth arguing with, but sadly I have seen my fair share of "professionals" also using the term. Maybe its me that's wrong.


You don't need professionals,we have 80%ers here who will argue the point until they're blue in the face.
Link Posted: 9/11/2010 6:46:55 PM EDT
[#20]
I've knocked a couple deer down with a .50 cal M.L. before.    They were close, and they were fairly little, but it still knocked them down.  
Link Posted: 9/11/2010 6:50:18 PM EDT
[#21]
Link Posted: 9/11/2010 6:52:37 PM EDT
[#22]
I'm in the "Shoot him" camp, too bad it's illegal.
Link Posted: 9/11/2010 6:52:41 PM EDT
[#23]
Quoted:

Quoted:
I've knocked a couple deer down with a .50 cal M.L. before.    They were close, and they were fairly little, but it still knocked them down.  

They fell over, not the same thing as knocking them over. I understand what you mean, I shot a deer that walked right under my stand from a few feet away with a 7mm rem mag and he fell over like he was hit by a truck, but he just toppled over from the sudden injury, there were not enough force pounds to actually knock him over-but it sure looked dramatic.


And here I thought penguins only hunted fish.
Link Posted: 9/11/2010 6:54:12 PM EDT
[#24]
Link Posted: 9/11/2010 6:54:33 PM EDT
[#25]
Quoted:
Quoted:
One of newton's laws says that every force has an equal an opposite force.

Therefore, in order for the round from a weapon to knock someone over, it would also knock whoever fired at them as well.


Im not sure this is correct (wouldnt the buffer, spring , operation have an effect?). I have seen some of the trauma left (with plates) and it is pretty substantial.

ETA: Also, at what speed is the bullet traveling at 4ft vs say 100yds.


Yes, the buffer and operation would absorb and spread out some of the energy.  Not a whole lot, but some.  A muzzle break, though, works even better.  It doesn't just spread out the recoil so that it's easier to take.  It puts the recoil energy into the weapon itself - it "stretches" the weapon.  You never feel the energy, because the weapon itself absorbs it.
Link Posted: 9/11/2010 6:55:31 PM EDT
[#26]





Quoted:



Thanks for the vids guys, anyone got any super science thing on the laser?





-V



To keep it basic, same idea... How much do focused light particles weigh?





ETA: Explosions due to parts going boom in spacecraft /=laser moving target





 
Link Posted: 9/11/2010 7:16:43 PM EDT
[#27]
Quoted:

Quoted:
I've knocked a couple deer down with a .50 cal M.L. before.    They were close, and they were fairly little, but it still knocked them down.  

They fell over, not the same thing as knocking them over. I understand what you mean, I shot a deer that walked right under my stand from a few feet away with a 7mm rem mag and he fell over like he was hit by a truck, but he just toppled over from the sudden injury, there were not enough force pounds to actually knock him over-but it sure looked dramatic.


When it spins them around 180*'s and 2-3 feet from the way they were when I squeezed the trigger I would call it knocking them down.   Especially when the slug impacts both shoulder blades at 5 yards on a 60 lb doe.    I've shot deer with everything from a bow to a .223 to a 30-06 so I'm familiar with them just "falling over".  

I guess it all comes down to debating the difference between toppling over and being knocked down.   If a deer is on the move then its momentum will carry it a ways too and that could be confused into the equation.  

For the sake of the argument at hand, a bullet will not knock someone down, I realize this.   Especially a fast round, it typically moves through the target too quickly and is too small in diameter.  

However, (and I'm not a scientist OR very good at math) there certainly must be a  point at which surface area of the bullet itself, the size (weight, density) of the target being shot and the velocity of the round would in fact knock something or someone over.   ie: if you shot a squirrel with a cannonball...

Link Posted: 9/11/2010 7:36:14 PM EDT
[#28]
I see, thanks guys. Yall taught me something. I thought the kinetic energy would knock em over.
Link Posted: 9/11/2010 7:41:22 PM EDT
[#29]



Quoted:


I'm in the "Shoot him" camp, too bad it's illegal.






 
Link Posted: 9/11/2010 7:46:34 PM EDT
[#30]
Quoted:
In an internet discussion with someone right now that is insisting that a bullet, when striking a vest and trauma plate has the inertia to knock someone off their feet because they've seen it in video from Iraq.

Anyone got any good scientific proof to refute this?

Also, in the same argument, he is stating that a laser in the 4+ megajoules range would strike a target in space so explosively that it would shift a 50 ton spacecraft and reverberate through the vessel.  The 50 ton vessel is the one being struck.

Ok hive, how about it?  Good proof on the bullet and good science geeky stuff on the lazorz...

-V



just remember that arguing on the internet is like running for president in 2008, even if you win you still look like an asshole

Link Posted: 9/11/2010 7:54:54 PM EDT
[#31]
Quoted:
I'll bet a nickel that after being confronted with absolute proof, he STILL wont believe it!


+1! Arguing with idiots is self-defeating. They will drag you down to their level and beat you with years of experience.
Link Posted: 9/11/2010 8:03:33 PM EDT
[#32]
Is there no such thing as science class in school anymore?  Or are they so busy teaching about global warming they can't be bothered with useless shit like real science?  For fuck's sakes.



Ask him about airplanes and treadmills next.
Link Posted: 9/11/2010 11:26:17 PM EDT
[#33]



Quoted:


Is there no such thing as science class in school anymore?  Or are they so busy teaching about global warming they can't be bothered with useless shit like real science?  For fuck's sakes.



Ask him about airplanes and treadmills next.


He is probably a truther, mentioning airplanes will lead him to 9/11 discussion



 
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