I think it would reflect very badly on both Microsoft and NBC if MSNBC's reporting had any hint of bias. It's smart for both of them to encourage impartiality (at least until they have our trust...:-).
Sorry, but you're wrong. Escape velocity is a property of ballistic flight. Powered vehicles are not constrained by escape velocity. I don't know what else to tell you.
Even if you are exerting a force, the force of Earth's graviation (or a Black Hole's or whatever) can still be greater and hold you in.
Ok, but what if your rocket's force is greater than the Earth's gravitation? Then you will escape that gravitation, regardless of your velocity.
I'm not sure I'll be able to explain any better this time, but I'll try. Let me start with what "escape velocity" really is...
If I am at a certain distance from a mass (like a planet), then my velocity determines the orbit that I will have around that mass. The higher velocity I have at a given point, the larger my orbit will be. Beyond a certain velocity, the orbit no longer forms a closed loop (ie. a circle or ellipse): it forms a parabola or hyperbola, and I fly out into space, never to return. The lowest velocity at which this occurs is called "escape velocity".
This all rests on the assumption that the only force involved is gravity. If the orbiting object is a powered vehicle, everything changes. Even if escape velocity is 7 miles per second (as it is at the surface of the Earth), a rocket could escape into space at one inch per second, as long as it has fuel to burn.
Let me be clear about that: a powered vehicle does not necessarily need to attain escape velocity in order to escape.
Thus, even though escape velocity is the speed of light at the event horizon, that is not relevant for powered vehicles. Hopefully my original post will now make more sense.
Since escape velocity is the speed of light and because relativity prevents you from accelerating to the speed of light, if you fall inside the event horizon then according to relativity you can't get back outside.
Are you sure? The event horizon is nothing more than the distance at which escape velocity is the speed of light. That prevents ballistic escape from behind the black hole, but as far as I can tell, it doesn't prevent powered escape.
Consider a Mars rocket taking off from Earth. Pick a point early in its take-off when it is travelling, say, one mile per second. Escape velocity from Earth is more like seven miles per second; since the rocket is not travelling this fast, it is tempting to say it won't escape. However, clearly the rocket does indeed escape. The reason is that the rocket is not ballistic: it is powered.
I don't see any reason that a powered rocket couldn't climb out of the event horizon while travelling slower than the speed of light.
However, I'm no expert on general relativity, so perhaps there are spacetime curvature/time dilation/whatever effects that I'm not accounting for.
If you had read the article, you'd know he's talking about application installation practices. Your installer sure as hell better distinguish Linux from Windows, for instance, so it can tell the difference between/etc and the registry.
If you're a systems administerator and don't know how to package applications, you need to learn because you need it to do your job.
Linux makes every home user a systems administrator. Are you saying every home user needs to learn how to package applications? I personally have no interest in doing that.
Sure, this stuff is more efficient than copper for conducting heat, meaning it has a low thermal resistance. However, to continue the electrical analogy, I wonder what would be the "thermal current" it could support? That is, how many watts could this material really dissipate? For all we know from the article, maybe if you try to put in more than a few watts per square inch, the stuff melts or catches fire.
I have met the Canadian cyborg, professor Mann, on a number of occasions (I almost took one of his courses) and I can testify that the concept of "functioning normally" applies to him only in the loosest of senses, even at the best of times.
Right on, brother. I used LaTeX for my thesis, and was disappointed. The idea of "programming" a document appeals to me greatly---I even did most of my thesis diagrams using nothing but hand-written PostScript---but I found that LaTeX is just not what it's cracked up to be.
Personally, I find MS Word easier from start to finish, with the appropriate use of Styles. The problem with that is its proprietary binary file format, which can get corrupted after a bad enough crash. Binaries don't work too well with revision control systems, so you end up just keeping vast quantities of backup copies.
HTML+CSS does a great job of separating content from presentation IMHO, but that's no good because (1) browsers (by which I mean MSIE of course) don't support it, and (2) it's no good for typesetting.
it would lose its small-community feel that Slashdot has also lost
You mean back in the good old days when you first joined, when it was only you and the 264,599 other users?
Re:FAQ from the SerialATA.org website
on
Serial ATA Coming
·
· Score: 2
Why the arbitrary distinction between internally and externally connected devices.
I don't think it's so arbitrary--one important difference is distance. Serial ATA goes to one meter, while (for instance) USB goes to about three meters. Less distance means you can get more throughput out of cheaper devices.
I didn't say all heat based power stations must be 50% efficient, and I'm not sure that's what the original poster was implying.
Funny, I thought that was exactly what was implying when he said "For any heat base power generation system, like nuclear, gas, coal, oil, the best efficiency that thermodynamics allows is 50%."
There is no practical way to convert 100% of heat energy into another form
Of course there isn't, but that's not the issue. I was arguing with the assertion that the maximum efficiency is 50%. I'm no expert either. I'm just trying to understand.
I don't buy it. What physics exactly are you referring to?
I understand that all energy ends up as heat, because that is the maximum-entropy state. What I don't get is how that implies that all heat-based power stations must be only 50% efficient.
If I have a 1GW station, then of course all that 1GW will eventually be heat, but hopefully much of it will become heat only after it reaches my home and warms up my CPU.
Slashdot Mirror
LOL! You just made my day.
I think it would reflect very badly on both Microsoft and NBC if MSNBC's reporting had any hint of bias. It's smart for both of them to encourage impartiality (at least until they have our trust... :-).
Hardly. People like to develop code to run on an operating system, not just a shell and a filesystem.
(This is probably a case of my tiny, 3D, Newtonian mind at work again...)
Thanks for the clarification. I was afraid that my understanding was insufficient, and you have demonstrated that my fears were justified. :-)
I'm not sure I'll be able to explain any better this time, but I'll try. Let me start with what "escape velocity" really is...
If I am at a certain distance from a mass (like a planet), then my velocity determines the orbit that I will have around that mass. The higher velocity I have at a given point, the larger my orbit will be. Beyond a certain velocity, the orbit no longer forms a closed loop (ie. a circle or ellipse): it forms a parabola or hyperbola, and I fly out into space, never to return. The lowest velocity at which this occurs is called "escape velocity".
This all rests on the assumption that the only force involved is gravity. If the orbiting object is a powered vehicle, everything changes. Even if escape velocity is 7 miles per second (as it is at the surface of the Earth), a rocket could escape into space at one inch per second, as long as it has fuel to burn.
Let me be clear about that: a powered vehicle does not necessarily need to attain escape velocity in order to escape.
Thus, even though escape velocity is the speed of light at the event horizon, that is not relevant for powered vehicles. Hopefully my original post will now make more sense.
Are you sure? The event horizon is nothing more than the distance at which escape velocity is the speed of light. That prevents ballistic escape from behind the black hole, but as far as I can tell, it doesn't prevent powered escape.
Consider a Mars rocket taking off from Earth. Pick a point early in its take-off when it is travelling, say, one mile per second. Escape velocity from Earth is more like seven miles per second; since the rocket is not travelling this fast, it is tempting to say it won't escape. However, clearly the rocket does indeed escape. The reason is that the rocket is not ballistic: it is powered.
I don't see any reason that a powered rocket couldn't climb out of the event horizon while travelling slower than the speed of light.
However, I'm no expert on general relativity, so perhaps there are spacetime curvature/time dilation/whatever effects that I'm not accounting for.
That was an easy +4 karma, wasn't it?
/etc and the registry.
If you had read the article, you'd know he's talking about application installation practices. Your installer sure as hell better distinguish Linux from Windows, for instance, so it can tell the difference between
Duh...
Slashdot: News for Nerds. Stuff that matters.
If you want balanced coverage of the Oscars (or anything else, for that matter) you have come to the wrong place.
Oops, my mistake. I suppose if they can use it as a truck radiator, it must have a pretty high capacity for dissipating heat. Never mind.
Someone mod the parent down for me...
Sure, this stuff is more efficient than copper for conducting heat, meaning it has a low thermal resistance. However, to continue the electrical analogy, I wonder what would be the "thermal current" it could support? That is, how many watts could this material really dissipate? For all we know from the article, maybe if you try to put in more than a few watts per square inch, the stuff melts or catches fire.
Check your sig. It's "repetitive".
I have met the Canadian cyborg, professor Mann, on a number of occasions (I almost took one of his courses) and I can testify that the concept of "functioning normally" applies to him only in the loosest of senses, even at the best of times.
Right on, brother. I used LaTeX for my thesis, and was disappointed. The idea of "programming" a document appeals to me greatly---I even did most of my thesis diagrams using nothing but hand-written PostScript---but I found that LaTeX is just not what it's cracked up to be.
Personally, I find MS Word easier from start to finish, with the appropriate use of Styles. The problem with that is its proprietary binary file format, which can get corrupted after a bad enough crash. Binaries don't work too well with revision control systems, so you end up just keeping vast quantities of backup copies.
HTML+CSS does a great job of separating content from presentation IMHO, but that's no good because (1) browsers (by which I mean MSIE of course) don't support it, and (2) it's no good for typesetting.
Where does that leave us? I wish I knew.
Doesn't it suck when you tell a joke, and someone mods you "informative"?
I don't buy it. What physics exactly are you referring to?
I understand that all energy ends up as heat, because that is the maximum-entropy state. What I don't get is how that implies that all heat-based power stations must be only 50% efficient.
If I have a 1GW station, then of course all that 1GW will eventually be heat, but hopefully much of it will become heat only after it reaches my home and warms up my CPU.