kingofthenet on 31/3/2006 at 07:30
Right, thats what I was thinking, because somewhere I read there was an idea for a space elevator, sorta like a regular one, but it would bring things into space cheaper per lb.So it COULD be done leaving a body with a slower than EV speed, but it's not practical, I read that WIKI entry, did I read it right, it sorta implyed that even if you were free of earth,as in moving earth Ev you might not have enough speed to leave the solar system? What mean distance from earth surface do you need to be at (roughly) to be considered free of earth(miles)
I wasn't really thinking about leaving earth as a problem, but say we develop some sorta "force field" shielding that can protect one's self from gravity, and heat, we could land on all sorts of super dense objects like white dwarfs or newtron stars, but getting the required EV for those objects would be hard, maybe they are 100000 times greater then the EV on earth
Agent Monkeysee on 31/3/2006 at 16:48
Quote Posted by kingofthenet
Agent Monkeesee, you seem knowlegable, answer me this one, what is Escape Volcity, and why is it important, I could never quite grasp it, lets say for shits and giggles, that for the earth it is 25,000 MPH, ok, so not to be really crazy, let say you are traveling away from the earth at 15,000mph still fast why wouldn't just take a little longer to do it? I have heard you would run out of fuel, but that doesn't seem right as it would depend on the "Type" of fuel and engine efficenency,what if you had a hose that supplied endless fuel, couldn't you Escape at like anything over 1mph, so long as you were making "foward" progress.
I guess this has already been largely answered but yeah escape velocity is the velocity an object would have to start at to escape a gravitational field without any additional force applied to it.
Like if you threw a ball. Your arm provides the initial velocity of the ball but after that there's nothing else exerting upwards acceleration on the ball. The only force acting on the ball at that point is gravity. If you wanted the ball to escape Earth's gravitational field you would have to throw it at 25,000 MPH.
As already mentioned this really doesn't have anything to do with rockets, since rockets are applying a constant thrust and thus provide a counteractive force to gravity. Technically if you had enough fuel a rocket could escape the Earth at 1 MPH. Or 1 foot/hour. Or 1 inch/hour. As long as the rocket's engine is exerting enough force to maintain
some upward velocity it could theoretically escape Earth's gravity.
Quote Posted by kingofthenet
One more on things like Newtron Stars, they say a cubic inch of material weighs as much as a 1,000 battleships, is that as a whole?, or if you could carve a piece out and bring it to earth would it still weigh that?
I don't know. How much something weighs is partly a function of what sort of gravitational field it's sitting in. So do they mean 1 cubic inch weighs as much as 1,000 battleships if this cubic inch is sitting in the neutron star's gravitational field or if it's sitting in Earth's gravitational field?
I'm gonna assume they're calculating the weight based on Earth's gravitational field, as neutron stars are dense stuff, but that's the problem with those little "SCIENCE FACTS!" soundbites. They hide a lot of detail that goes into framing the answer.
Quote Posted by kingofthenet
I wasn't really thinking about leaving earth as a problem, but say we develop some sorta "force field" shielding that can protect one's self from gravity, and heat, we could land on all sorts of super dense objects like white dwarfs or newtron stars, but getting the required EV for those objects would be hard, maybe they are 100000 times greater then the EV on earth
If you created some magic science bubble that protected you from the crushing power of a neutron star then it would also protect you from any consideration of escape velocity, as it's the same force in both cases.
Para?noid on 31/3/2006 at 18:34
spell it newtron star one more fucking time and i am going to find your house and kill you
kingofthenet on 31/3/2006 at 21:31
Quote Posted by Para?noid
spell it newtron star one more fucking time and i am going to find your house and kill you
neutron star neutron star neutron star neutron star neutron star
You know how it is u and w are so close on a keyboard... LOL
Bjossi on 31/3/2006 at 21:44
Neutron stars are just a mass of a star compressed to a tiny ball, around 25 Kms across. One teaspoon of the matter weights a lot, millions of tons as far as I know.
I´m digging up old memories so I may be wrong. :eww:
dj_ivocha on 1/4/2006 at 02:55
Quote Posted by Agent Monkeysee
If you created some magic science bubble that protected you from the crushing power of a neutron star then it would also protect you from any consideration of escape velocity, as it's the same force in both cases.
Would it? You would be protected inside the bubble, but you'd have to remain in it all the way until you are out of the crushing gravitational force. The bubble would have to move with you, but it is not protected by the gravity as you are, so you (the whole system, comprised by you and the bubble) would need the same escape velocity as without such a bubble.
Right? :confused:
Mingan on 1/4/2006 at 04:11
of course not, it's a magic science bubble.
dj_ivocha on 1/4/2006 at 07:33
Oh, didn't notice the "magic" part. :(
Carry on.
Agent Monkeysee on 1/4/2006 at 09:54
Quote Posted by dj_ivocha
Would it? You would be protected inside the bubble, but you'd have to remain in it all the way until you are out of the crushing gravitational force. The bubble would have to move with you, but it is not protected by the gravity as you are, so you (the whole system, comprised by you and the bubble) would need the same escape velocity as without such a bubble.
Right? :confused:
The force that would be crushing you is gravity. The force that you need escape velocity to break from is gravity. If the bubble protects you from gravity it protects you from both being crushed and from needing an escape velocity.
I suppose unless the mechanism for resisting the crushing is that your bubble is really structurally sound or something. I was under the impression kingofthenet was describing something that simply nullified gravitational effects.
edit: no on second thought that wouldn't work. It would have to completely nullify gravitational effects within the bubble to keep you from being crushed.
Shug on 1/4/2006 at 17:49
shut up monkeysee u ignorant git
