The no topic thread

JamJonesin' · **Posted:** Thu May 17, 2012 10:05 pm

odman wrote:

DirtyBill342 wrote:

Unless a snake falls in your canoe! Which has actually happened to me.... while canoeing... in VA :lol:

True story.

Didn't they make a movie about that?

I think that was West VA....."Sher do got a purty mouth"

phorevergr8ful · **Posted:** Fri May 18, 2012 1:52 am

Where you goin city boy?

odman · **Posted:** Sun Jun 10, 2012 3:34 pm

Riding that train...

Filmed a ride on the MagLev from Shanghai to Pudong airport. The quality is terrible but it's pretty cool to ride a train at 269 mph.
So what does this have to do with jam cruise? Everything. See, normal trains only go to 10, right? So where do you go from there?

phorevergr8ful · **Posted:** Mon Jun 11, 2012 1:03 am

So how fast would you be traveling if you ran from the back of the car to the front?

Tai · **Posted:** Mon Jun 11, 2012 10:30 am

phorevergr8ful wrote:

So how fast would you be traveling if you ran from the back of the car to the front?

it's all relative. :SHIFTY:

audionaut · **Posted:** Mon Jun 11, 2012 1:00 pm

Tai wrote:

phorevergr8ful wrote:

So how fast would you be traveling if you ran from the back of the car to the front?

it's all relative. :SHIFTY:

JC = MC squared

odman · **Posted:** Mon Jun 11, 2012 2:36 pm

<RANT>Can you believe that one individual, one single miserable son-of-a-ho, had the audacity, the balls, the chutzpah to unlike my video on Youtube? WTF? You bloody try to keep a camera still when the train is shaking all over the place at half the speed of a jetliner. This is outrageous!!! </RANT>

I once had the following physics discussion. Nobody could quite pinpoint the answer until we finally found a gun maker that could answer it. Although the discussion was about sitting at the back of an airplane, with the speeds of Maglev it could be as relevant.
Here it is. Assume you stand at the end of the train with a gun aiming backwards. This hypothetical train runs at exactly the same speed as the exit velocity of the bullet.
Relative to the ground, at the time of firing, the bullet will:
- fly backwards
- fly forwards (following the train)
- drop straight down

I need to know so I can shoot the MoFo who unliked my youtube! :evil:

Tai · **Posted:** Mon Jun 11, 2012 3:05 pm

next you are going to ask if an airplane can take off from a treadmill. :shock:

The answer is 'none of the above', it will embed itself in the rear wall of the cabin and then travel forward with the vehicle, no flying, no dropping.

audionaut · **Posted:** Mon Jun 11, 2012 3:18 pm

Tai wrote:

next you are going to ask if an airplane can take off from a treadmill. :shock:

The answer is 'none of the above', it will embed itself in the rear wall of the cabin and then travel forward with the vehicle, no flying, no dropping.

I saw that mythbusters too :oops:

...but what Odman's discussion was if the person was outside the car standing on the back of the train... his name might be Yosemite Sam... etc... this is a good no topic!

Tai · **Posted:** Mon Jun 11, 2012 3:56 pm

audionaut wrote:

Tai wrote:

next you are going to ask if an airplane can take off from a treadmill. :shock:

The answer is 'none of the above', it will embed itself in the rear wall of the cabin and then travel forward with the vehicle, no flying, no dropping.

I saw that mythbusters too :oops:

...but what Odman's discussion was if the person was outside the car standing on the back of the train... his name might be Yosemite Sam... etc... this is a good no topic!

well, in that case, "The bullet went that-a-way, George".

Bruce · **Posted:** Mon Jun 11, 2012 11:13 pm

Yeah, the bullet is falling to the ground at the same rate whether you shoot it or drop it from your hand.

But, what if Schrödinger's cat pull's the trigger :THINK:

Shourryya Ray, a 16-year-old German student, has cracked a puzzle that Sir Isaac Newton first posed more than 350 years ago.

Physicists have previously only been able to approximate by using computers with partial solutions. The teen's solutions allow exact calculations of a trajectory under gravity and subject to air resistance. In other words, an item's flight path can be calculated and predictions can be made about how the object will hit and bounce off a barrier. The two questions were first posed in the 17th and 19th centuries.
http://www.ottawacitizen.com/technology/Teen+solves+Newton+year+riddle/6685617/story.html

odman · **Posted:** Tue Jun 12, 2012 2:15 am

Isn't that typical the lamestream media. Oh, the equation of the century. Can they show it. Oh fuck no. Hate shit like that.

Anyhow, the answer to my "riddle":
The exit velocity of a typical 9mm round is in the range of 700-800 mph, so there is really no train (or even commercial jet) that could be used for this experiment. But this is theory so everything is possible.

In physics, almost everything is relative and can be calculated backwards. Sometimes it's easier to understand by a simple thought experiment:
If you hold the gun perfectly still, the bullet will leave the gun with say 750 mph.
Now let's look at this from the bullet's point-of-view. The bullet is now still and the gun is moving (relatively) away with 750 mph (Note, I'm not talking conservation of linear momentum here, just relative velocity)
Now say that you want that gun to fly at exactly the same speed as a passing train. Well obviously that train would have to move at 750 mph as well. And this is what was given in the original question.
So by pure logic reasoning, we find that:
If the train moves +750 mph (in one direction), the gun also moves at +750 mph. The bullet leaves the gun at -750 mph. The ground is not moving (relative to the observer), so an observer standing on the ground exactly at the place and moment when the gun is fired will see the bullet falling straight down.

Foot notes, disclaimers and caveats:
1) The above is true for passive ammunition, that is all the momentum given to the projectile happens inside the barrel. If instead you fire a missile from the back of the train, the missile will keep accelerating after it has left the weapon. It may move backwards and even fly away if it has enough acceleration. It is true however that in the exact moment the missile is fired it will have a zero velocity relative to the ground.

2) In reality, if you actually could find a fast enough vehicle to shoot from, the bullet will land somewhat forward (along the train direction) relative to the observer because of the air suction caused behind the moving vehicle. As we are only discussing the infinitesimal time of the bullet leaving the barrel, such details are concidered irrelevant. At that instant in time the bullet falls straight down in front of the observer.

3) If you shoot forward from the front of the train the bullet will indeed in this
experiment leave the barrel with double the speed of the train (as long as you stay comfortably far below the speed of light..)

phorevergr8ful · **Posted:** Tue Jun 12, 2012 2:33 am

I think the Improbability Drive would come in handy here. :THINK:

Bruce · **Posted:** Tue Jun 12, 2012 5:13 am

Restaurant At The End Of The Universe

pt2 http://youtu.be/vI8GtDlW7X4
pt3 http://youtu.be/4R7aI_aZxiU
pt4 http://youtu.be/Rzi10uDAGo4 final

Arthur Dent:
Hitchhiking the Galaxy in his robe. Serving both as a towel and an informal garment.

LIRR · **Posted:** Tue Jun 12, 2012 10:03 am

so craving some rack of lamb!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

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