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Originally posted by adam warlock
But that doesn't work either. In space, friction is very low and we can neglect it. Stopping the engines would mean that a 0 net force is applied to the spaceship and so the space ship shouldn't stop but to continue in its state of movement with a constant velocity.
No, stopping is applying enough force to a body so that it stops moving (relative to some frame of reference, obviously). So it would mean firing the appropriate thrusters in order to match the velocity of some particular body that is used as the reference point for "stopped."

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Originally posted by convect
No, stopping is applying enough force to a body so that it stops moving (relative to some frame of reference, obviously). So it would mean firing the appropriate thrusters in order to match the velocity of some particular body that is used as the reference point for "stopped."
Unless the ship was using the engines to maintain a non-geostationary orbit.

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Originally posted by convect
No, stopping is applying enough force to a body so that it stops moving (relative to some frame of reference, obviously). So it would mean firing the appropriate thrusters in order to match the velocity of some particular body that is used as the reference point for "stopped."
I know all of that, but Palynka talked about stopping the engine not to make them go in the opposite direction of the movement.

But even that method wouldn't work in space.

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Originally posted by adam warlock
But that doesn't work either. In space, friction is very low and we can neglect it. Stopping the engines would mean that a 0 net force is applied to the spaceship and so the space ship shouldn't stop but to continue in its state of movement with a constant velocity.
Ok, you're asking for it. 😠

FIRST, in any case the engines would be stopped. That's the point of the order. Why waste fuel if there's nowhere to go? SO, the order to stop is still meaningful under that interpretation.

SECOND, Andrew criticism applies to your post. What is movement, if there are no external points of reference? If "stopping one's movement" is meaningless, then for the same reason so is any claim "to continue in its state of movement".

THIRD, do you like them apples?

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Originally posted by Palynka
Ok, you're asking for it. 😠

FIRST, in any case the engines would be stopped. That's the point of the order. Why waste fuel if there's nowhere to go? SO, the order to stop is still meaningful under that interpretation.

SECOND, Andrew criticism applies to your post. What is movement, if there are no external points of reference? If "stopping one's movem ...[text shortened]... is any claim "to continue in its state of movement".

THIRD, do you like them apples?
First point:
$But the spaceship wouldn't stop. So the order all stop wouldn't be respected would it? And I think you making up an interpretation just to be right. Who in his right mind would say: "All stop" and not expect is velocity to go to 0 (to respect to a given frame of course)

The OP said that the spaceship stopped in the episode in question and that can't be done by just stopping the engines. That's why I said that stopping the engines wouldn't do it.


Second point:
So the stars went out, or stopped existing? I thought they just went out. If so they still have a gravitational influence in the spaceship and can be taken as outside references in order to define a frame. Besides I think that even though the stars went out the spaceship still had their positions recorded and so could stop relative to that frame.

I can even more pedantic than that 😉

How do you like them apples?

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Originally posted by adam warlock
First point:
$But the spaceship wouldn't stop. So the order [b]all
stop wouldn't be respected would it? And I think you making up an interpretation just to be right. Who in his right mind would say: "All stop" and not expect is velocity to go to 0 (to respect to a given frame of course)

The OP said that the spaceship stopped in the e.

I can even more pedantic than that 😉

How do you like them apples?[/b]
Pfft.

"All stop" is clearly for the engines. Why "All" if it was for the single ship? No, "all" OBVIOUSLY refers to "all engines". Do I have to explain everything?

The OP said that the spaceship [b]stopped in the episode in question and that can't be done by just stopping the engines. [/b]
He cannot know if it stopped or not if there are no external points of reference. What he CAN know is whether the engines stopped or not (i.e. no engine noise or thrusters being off). That's HIS mistake if he interprets it as a conventional stop.

So the stars went out, or stopped existing?
It is my interpretation that they were in another dimension where they stopped existing (well, didn't exist actually). If not, then his criticism is again invalid as there would be external objects for which to measure relative movement even if the relative movement is infinitesimal relative to the position of such stars.

Letting them apples fall on your head won't turn you into Newton. 😏

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Originally posted by Palynka
Pfft.

"All stop" is clearly for the engines. Why "All" if it was for the single ship? No, "all" OBVIOUSLY refers to "all engines". Do I have to explain everything?

[b]The OP said that the spaceship [b]stopped
in the episode in question and that can't be done by just stopping the engines. [/b]
He cannot know if it stopped or not if there are ...[text shortened]... such stars.

Letting them apples fall on your head won't turn you into Newton. 😏[/b]
This is fun. 😉

"All stop" is clearly for the engines
Really? I didn't know that. 😳 And I'm not being sarcastic. I thought that all stop was equivalent to say full stop. But are you really sure this is the correct interpretation? And don't try to throw any sand into my eyes Mister.

He cannot know if it stopped or not if there are no external points of reference. What he CAN know is whether the engines stopped or not (i.e. no engine noise or thrusters being off). That's HIS mistake if he interprets it as a conventional stop.


Au contraire my dear friend. So even in the case of the disappearing stars we have this: Engines are running so this means a net force different than 0 is being applied to the spaceship. This means that the ship isn't an inertial frame. But when the engines stop the ship is an inertial frame. And we can distinguish inertial frames by doing physical experiments. Just imagine Data letting a ball drop when the engines are on. Due to the spaceship acceleration the ball would drop not only vertically but also with a backwards (relative to the direction of motion of the spaceship) component. When the engines are off Data would drop the same ball and it would fall in a perfect vertical way; thus Captain Picard would know that his space ship was now an inertial frame and would be stopped relative to some other inertial frame. If this said inertial frame was or wasn't the previously present stars is another matter.

So, you see that in principle there are ways to distinguish both types of movement in this case.

Apple pie is good enough for ya? 😛

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Originally posted by adam warlock
This is fun. 😉

[b]"All stop" is clearly for the engines

Really? I didn't know that. 😳 And I'm not being sarcastic. I thought that all stop was equivalent to say full stop. But are you really sure this is the correct interpretation? And don't try to throw any sand into my eyes Mister.

He cannot know if it stopped or not if t ...[text shortened]... of movement in [b]this case.

Apple pie is good enough for ya? 😛[/b][/b][/b][/b][/b][/b]
BUT, that's just in principle. Since such an experiment was not conducted, we cannot, in good faith, conclude that Star Trek was wrong.

Besides, everybody knows that Star Trek is REAL. 😛

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Originally posted by adam warlock
This is fun. 😉

"All stop" is clearly for the engines
Really? I didn't know that. 😳 And I'm not being sarcastic. I thought that all stop was equivalent to say full stop. But are you really sure this is the correct interpretation? And don't try to throw any sand into my eyes Mister.

He cannot know if it stopped or not ...[text shortened]... t guish both types of movement in [b]this case.

Apple pie is good enough for ya? 😛[/b]
Just imagine Data letting a ball drop when the engines are on. Due to the spaceship acceleration the ball would drop not only vertically but also with a backwards (relative to the direction of motion of the spaceship) component. When the engines are off Data would drop the same ball and it would fall in a perfect vertical way

No, the ships anti-grav system clearly nullifies such an experiment. If it didn't the crew would all be pushed towards the back of their seats when the engines were on. You would not have people standing around as if the only force acting on them was gravity. So Data's ball will drop vertically whether the ship is accelarating or not.

And even if you could see the stars, you would have to frame your 'stop' command relative to one of them, since they are all moving relative to each other. In the absense of an external frame of reference, such as a star, 'all engines stopped' is just as good as 'ship stopped'.

In fact, if you do have a frame of reference, such as a star, nearby then 'ship stopped' relative to the star will be different to 'all engines stopped' since the engines will need to be running to maintain the ships position in the star's gravity well.

In space, the command 'all stop' with no other information can only mean 'all engines stop'.

--- Penguin.

Is the apple falling down to the Earth or is the Earth falling up to the apple?

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Please, tell me about the Star Trek gravity. All planets seems to have almost the same gravity, no matter the size. Have all planets their own grav- or, anti-grav equipment?

And what about these wrecked spaceships with 1G grav. Never mind their life supporting system is out, energy production is out, the grav is always 1G.
Have they invented some permanent grav-device, like permanent magnets doesn't lose their magnetism even if any outside energy source is cut off?

Or is it just StarTrek technology that this work?

If so, then ships can go aerodynamically with sound too, their technology gives far more advanced things than some fancy manouevres and noice...

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Originally posted by FabianFnas
Please, tell me about the Star Trek gravity. All planets seems to have almost the same gravity, no matter the size. Have all planets their own grav- or, anti-grav equipment?

And what about these wrecked spaceships with 1G grav. Never mind their life supporting system is out, energy production is out, the grav is always 1G.
Have they invented some perm nd too, their technology gives far more advanced things than some fancy manouevres and noice...
All planets seems to have almost the same gravity, no matter the size. Have all planets their own grav- or, anti-grav equipment?

Obviously not. They simply have different densities leading up to having similar mass/distance^2 ratio.

And what about these wrecked spaceships with 1G grav.
Which episode?

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Originally posted by Palynka
And what about these wrecked spaceships with 1G grav.

Which episode?
Don't remember, there hae been several of them. Twisted metal parts, debris evrywhere, dead people, always one unconsious man, or boy, that needs help. But the rescued person talks fluently English.

Well, a wreck with nothing functioning shouldn't have any gravitation at all, as it is floating in free space.

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Originally posted by FabianFnas
Don't remember, there hae been several of them. Twisted metal parts, debris evrywhere, dead people, always one unconsious man, or boy, that needs help. But the rescued person talks fluently English.

Well, a wreck with nothing functioning shouldn't have any gravitation at all, as it is floating in free space.
Until you can provide me with an example where this happened in Star Trek, I'll file this under "slander".

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Originally posted by Palynka
Until you can provide me with an example where this happened in Star Trek, I'll file this under "slander".
You take this far to seriously. Star Trek is only SF, their technology is invented by SF writers. Most of the StarTrek technology will never be invented. Just file it under "slander" if the file is not full already. 🙂

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Originally posted by FabianFnas
if the file is not full already. 🙂
They take out the trash twice a week here.

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