Naked Science Forum
General Science => General Science => Topic started by: dentstudent on 31/05/2007 11:24:38
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I'm sure it would be an uncomfortable climb, but, hypothetically, is it possible?
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Yes, although you wouldn't be able to make the ladder strong enough. If you let go you would still fall as you wouldn't have the speed to orbit, until you were up nearly as high as geostationary orbit.
This is essentially the idea behind a space elevator, but the idea is to hang the ladder from a large mass beyond geostationary orbit. However the materials reqirements on the cable are almost impossible to achieve.
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I was wondering if you would burn up trying to leave the atmosphere, and I found this link
http://www.thenakedscientists.com/forum/index.php?topic=3792
Apparently the heat that is generated by enetering the atmosphere is due to friction or drag, so you would probably be fine if you had enough oxygen.
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You'd start to boil as the pressure reduced with altitude (eyes popping out and all that) so I guess you'd have to pack a big overnight bag to carry all the gear (oxygen, spacesuit, food)..! I wonder how long it would take?
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You'd start to boil as the pressure reduced with altitude (eyes popping out and all that) so I guess you'd have to pack a big overnight bag to carry all the gear (oxygen, spacesuit, food)..! I wonder how long it would take?
It would take a long time. Consider that to get to geostationary orbit, you'd have to climb approximately 40,000 km straight up. Imagine having to walk that distance on the Earth (almost twice around the Earth at the equator), then imagine that you're climbing a ladder wearing a space suit.
Kim Stanley Robinson wrote an excellent trilogy about the terraforming of Mars. In this book, a space elevator was constructed on Mars in which you could ride between the surface and space. This ride took several days.
Dick
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Space starts about 60 miles up (definitions vary). OK, a 60 mile ladder climb would be very hard work but there's no reason why (with a strong enough ladder) you couldn't go by car. Modern racing cars generate downforce to help them corner at speed. In some instances this is more than the weight of the car. If you got one of these cars and drove it up a curved ramp fast enough (this things going to take some fuel and a big engine) then onto a vertical flat plate (the "ladder") you could drive up into space in much less than an hour. Remember to take a parachute. (I'm banking on the fact that, as you go up, while there's less air to create the "downforce2 that holds you to the ladder there's also less gravity and less drag so you can go faster. I'm not sure this would work.
OK, let's try to get round that problem if you are prepared to modify the car a bit then any car could do the job provided that it had a low enough gear. You would need something to hold you onto the "ladder" a big magnet and a steel ladder would work. Remember to pack enough air for yourself and the car's engine.
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Space starts about 60 miles up (definitions vary). OK, a 60 mile ladder climb would be very hard work but there's no reason why (with a strong enough ladder) you couldn't go by car. Modern racing cars generate downforce to help them corner at speed. In some instances this is more than the weight of the car. If you got one of these cars and drove it up a curved ramp fast enough (this things going to take some fuel and a big engine) then onto a vertical flat plate (the "ladder") you could drive up into space in much less than an hour. Remember to take a parachute. (I'm banking on the fact that, as you go up, while there's less air to create the "downforce2 that holds you to the ladder there's also less gravity and less drag so you can go faster. I'm not sure this would work.
OK, let's try to get round that problem if you are prepared to modify the car a bit then any car could do the job provided that it had a low enough gear. You would need something to hold you onto the "ladder" a big magnet and a steel ladder would work. Remember to pack enough air for yourself and the car's engine.
If one is going to use mechanical aids, then could you not just put a pulley at the top of the ladder, a long rope, and get pulled up, and so avoid the need to carry the engine and the fuel up with you?
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So, some sort of counterbalance structure - Or how about one of those magnetic monorailways - but as the weight increases, does this not mean that there has to be some sort of escape velocity? Or perhaps not, as the vehicle is actually pulling on something.
The racing car theory - yes I've often heard the quote about downforce, and that it would be possible to drive the car upside down with it sticking to the ceiling - now, why hasn't anyone built an upside down road to test this? It would make formula 1 more interseting!
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So, some sort of counterbalance structure - Or how about one of those magnetic monorailways - but as the weight increases, does this not mean that there has to be some sort of escape velocity? Or perhaps not, as the vehicle is actually pulling on something.
Escape velocity is largely an irrelevant issue in rocketry.
What matters is escape energy (how much energy you need to lift an object from the surface and send it infinitely far away), and that is unavoidable. All that escape velocity means is that if all of your energy is bound of the the initial velocity of the projectile (as it is when you fire a cannon shell, and having fired the shell, all the energy of that shell is imparted in it as it leaves the muzzle of the gun) then it describes what is the velocity you need to contain that energy.
With a rocket (or racing car driving up a ladder), you are constantly adding to the kinetic energy by constantly converting more chemical energy to kinetic energy. So you still have the same minimum requirement for the amount of energy required to escape the objects gravity, but it is not all bound up in the initial velocity, but rather is carried up in the chemical propellent, and that chemical energy keeps on being used to add more speed as you lose speed in the ascent.
Ofcourse, when you are in orbit around the Earth, you have not actually escaped the Earth's gravity; so even there, the notion of escape energy is not that meaningful. It is only when you start talking about interplanetary travel that you really are concerned about escape energy.
The racing car theory - yes I've often heard the quote about downforce, and that it would be possible to drive the car upside down with it sticking to the ceiling - now, why hasn't anyone built an upside down road to test this? It would make formula 1 more interseting!
Fine so long as you maintain your speed, but could be a problem as you slow down, and reduce your downforce (or should that be upforce in that case), and then fall off the ceiling.
All that the downforce is is the force generated by upside down aircraft wings. Any aircraft can fly, but only so long as the wings keep moving fast enough to keep the aeroplane in flight. Turning a racing car upside down effectively turns it into an aeroplane as far as the aerodynamic forces are concerned.
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"Fine so long as you maintain your speed, but could be a problem as you slow down, and reduce your downforce (or should that be upforce in that case), and then fall off the ceiling."
I was thinking about banking track, a bit like at Indinapolis, but that carried right over and out again in a loop before you slowed too far. Obviously, all speculation! But of anyone, Bernie Ecclestone has the money to do it!