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17th April 2019, 03:19 PM | #161 |
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Test questions for our thread starter to calibrate what we are dealing with.
Earth shape. Flat, round or other? Is space real? When we see the ISS passing overhead, what are we seeing? Why are all developed countries lying about the reality of space flight? Why are physicists and engineers lying about space flight? If communication satellites are not real, what are all those satellite dishes pointed at? |
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45 es un titere |
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17th April 2019, 03:50 PM | #162 |
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17th April 2019, 03:59 PM | #163 |
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17th April 2019, 04:01 PM | #164 |
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17th April 2019, 04:05 PM | #165 |
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17th April 2019, 04:13 PM | #166 |
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There is no Antimemetics Division. |
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17th April 2019, 04:16 PM | #167 |
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17th April 2019, 04:19 PM | #168 |
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I know I was a mod there for many years.
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17th April 2019, 04:32 PM | #169 |
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I wish you'd come back, at least to the modeling thread.
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17th April 2019, 05:08 PM | #170 |
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17th April 2019, 05:39 PM | #171 |
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Kittens. Thread needs kittens. And recipes. Kitten recipes.
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...our governments are just trying to protect us from terror. In the same way that someone banging a hornets’ nest with a stick is trying to protect us from hornets. Frankie Boyle, Guardian, July 2015 |
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17th April 2019, 06:06 PM | #172 |
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rocket cannot propel in the vacuum of space
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17th April 2019, 06:20 PM | #173 |
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My wife and I often help groups of kids, sometimes as young as first graders, build and launch model rockets. During the build sessions, we describe some of the fundamentals of how rockets work. Most of the kids seem to understand. Not sure why it would be so challenging to an adult.
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17th April 2019, 06:44 PM | #174 |
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"Common sense is the collection of prejudices acquired by age eighteen" - Albert Einstein "... education as the means of developing our greatest abilities" - JFK |
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17th April 2019, 06:59 PM | #175 |
Potsing Whiled Runk
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17th April 2019, 07:05 PM | #176 |
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17th April 2019, 07:15 PM | #177 |
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There's your problem right there. NASA cannot have a 'website' because there is no 'web'. The 'internet' idea did not work. In 1969, DARPA sent an L and an O and the connection crashed. They were never able make the connection again due to entropy. The computer people had completely disregarded the T deltaS term in their programming. All their messages were lost, broken into pieces as they left their computers. They later claimed that these pieces were in fact 'packets', but few believed such an obvious coverup. In 1991 European scientists were assigned the job of creating an improved cover and came up with this 'web' idea, which they implemented by sending out operatives to load fake graphics (95% of which was porn, by the way) onto personal computers around the world. So I would not believe anything you get from this 'website' you talk of.
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A Novel and Efficient Synthesis of Cadaverine Organic chemistry, vengeful ghosts, and high explosives. What could possibly go wrong? Now free for download! http://www.scribd.com/doc/36568510/A...-of-Cadaverine |
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17th April 2019, 07:37 PM | #178 |
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Obviously, that means cats are indeed evil and that ownership or display of a feline is an overt declaration of one's affiliation with dark forces. - Cl1mh4224rd |
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17th April 2019, 08:27 PM | #179 |
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And these people are smart enough to know the difference between real science and a hoax, so the conclusion is obvious - they're in on it!
But how could NASA have managed to keep this hoax a secret for all these years? Surely someone would have figured it out by now? Well now someone has (or is about to) so we might as well come clean and tell the truth. You see, Gingervytes, the reason NASA has no trouble with people finding out about their hoax is that we are all in on it - every single person in the Universe - except you. But that's not all. Your mathematical proof that the thrust equation is false is entirely correct - in the real World. But you are not in the real World. You are actually in The Matrix, and the rest of us are computer simulations created by thought-capable machines to control you while using your body as an energy source. Actually I lie. You don't have a whole body anymore, you're just a brain in a jar. Don't believe it? OK you got me. The Real Truth this time - you are actually just a computer simulation that we created to test the Matrix's defenses against trolls spouting nonsense (seems to be holding up OK so far...). Or... perhaps you are not a computer simulation inside The Matrix, NASA isn't covering up a vast conspiracy, and rockets do work in space. Which scenario do you think is more likely? |
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17th April 2019, 08:35 PM | #180 |
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If you're not a scientist but you think you've destroyed the foundation of a vast scientific edifice with 10 minutes of Googling, you might want to consider the possibility that you're wrong. Its TRE45ON season... convict the F45CIST!! |
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18th April 2019, 02:23 AM | #181 |
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On ignition, the rocket blew off a solid chunk of itself off. Pressure built up between the chunk and rocket. Like firing a gun, yes there is recoil because pressure builds up between the gun and bullet. The pressure pushes the bullet out and in turn pushes the gun. A rocket is like a gun firing a blank. The powder burns and moves out of the barrel only pushing off the air (assuming the gun powder was not encased in anything). Furthermore, the chamber fills up with smoke quickly and thus releasing any vacuum
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18th April 2019, 02:27 AM | #182 |
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18th April 2019, 02:54 AM | #183 |
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18th April 2019, 03:25 AM | #184 |
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18th April 2019, 03:44 AM | #185 |
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Remove the bullet from the cartridge... be careful!
https://www.youtube.com/watch?v=PQ25g0Whgt0 Slip the cartridge into the chamber, point the gun in a safe direction and fire the weapon. When you've done that, report back what you felt. |
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If you're not a scientist but you think you've destroyed the foundation of a vast scientific edifice with 10 minutes of Googling, you might want to consider the possibility that you're wrong. Its TRE45ON season... convict the F45CIST!! |
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18th April 2019, 03:46 AM | #186 |
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18th April 2019, 03:53 AM | #187 |
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rocket cannot propel in the vacuum of space
Let me jump the gun :-). I am sure, he will report feeling a recoil, but it happened only because the propellant pushed against the surrounding air. IF it was in vacuum, there would be no recoil :-). He, of course, can't prove it, because he doesn't have a vacuum chamber.
Taking bets? Anyway, I consider highly irresponsible giving somebody with Gingervytes' technical expertise any ideas about playing with guns and ammunition. |
18th April 2019, 03:54 AM | #188 |
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If you're not a scientist but you think you've destroyed the foundation of a vast scientific edifice with 10 minutes of Googling, you might want to consider the possibility that you're wrong. Its TRE45ON season... convict the F45CIST!! |
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18th April 2019, 03:57 AM | #189 |
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There are two things that I will never bet against...
1. Certainty 2. Stupidity I've always wondered why, if rockets don't work in a vacuum, aerospace companies like SpaceX make specially modified versions of their rocket engines with a larger exhaust section and a significantly larger expansion nozzle to maximize the engine's efficiency in the vacuum of space. Left to right: Falcon 1 Merlin 1C, Falcon 9 Merlin 1C and Falcon 9 M-Vac 1C without extension nozzle - and this is the extension nozzle |
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If you're not a scientist but you think you've destroyed the foundation of a vast scientific edifice with 10 minutes of Googling, you might want to consider the possibility that you're wrong. Its TRE45ON season... convict the F45CIST!! |
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18th April 2019, 03:58 AM | #190 |
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If, of course, he did have a vacuum chamber, then he'd claim that the initial expulsion of gas fills the chamber leaving some gas present in it for the remaining gas to push against. This is not an educational issue, it's either a matter of irrational belief or of deliberate contrarianism for the purpose of attention seeking.
When the outcome is predetermined, that's always a bad idea for one of the parties involved. Dave |
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18th April 2019, 04:17 AM | #191 |
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What do you mean by solid chunks?
Why does it matter if it is solid or if it is in a chunk? |
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18th April 2019, 04:23 AM | #192 |
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18th April 2019, 05:08 AM | #193 |
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Questions, comments, queries, bitches, complaints, rude gestures and/or remarks? |
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18th April 2019, 05:25 AM | #194 |
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Gingervytes, I took another look at your derivation. Your math isn't necessarily wrong (though that Ve=V is dangerous because it's not necessarily true anywhere but the exit point), but your interpretation is confused. While Ve is no longer explicit in the final formulation, it's still implied.
Try this: Make a little diagram with a pipe diameter and a fluid density and a Ve and calculate the force. Now, change just Ve and calculate the force again. It'll be different, because when you change Ve, Mdot will change too. So Ve still matters, it's just not explicit. |
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18th April 2019, 05:39 AM | #195 |
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Stopped watching when three incorrect statements had been claimed. That was before the two minute mark.
1) Flow under pressure. The pressure is against something. That is your equal and opposite force (and what propels a rocket, in air as well as in vacuum). 2) An object falling under gravity. Silly claim that the opposite force should be against whatever dropped the object. Of course it is not. The force of gravity works between two masses. In the case in question, it is the falling object and Earth. Earth pulls down on the object and the object pulls up on the Earth (but as the Earth is a zillion times more massive that the object, the object moves while Earth stays virtually unperturbed). 3) Buoyancy. The pressure is between different parts of the fluid. As the floating object is less dense than the fluid, the downwards pressure it exerts is less than the upwards pressure the fluid exerts on it. Displacement of masses happen within the fluid. #2 and #3 are totally irrelevant for the discussion of rockets. Hans |
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18th April 2019, 05:47 AM | #196 |
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Pressure gradient is your keyword. The gas is under pressure in the combustion chamber. As it exits the nozzle it is accelerated because the outside pressure is low, or zero. The push on the rocket comes from accelerating the gas.
You might intuitively think that a solid (and hence dense) object like a bullet being accelerated would cause more push, but you would be mistaken: The burning fuel releases a given amount of energy, which is directed towards the nozzle/barrel. The density of the mass accelerated will determine the velocity it attains, but the energy will be the same. And hence the opposite energy accelerating the rocket will also be the same. Hans |
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Experience is an excellent teacher, but she sends large bills. |
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18th April 2019, 05:51 AM | #197 |
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18th April 2019, 05:52 AM | #198 |
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But many of the demonstrations of Newton's third law on Earth involve moving solids, not gases.
Regardless, gas has mass. Therefore moving gas must have momentum. That momentum is calculable. It is a firm fact of physics that momentum must be conserved. Amid all your attempts to muddy the waters with irrelevant analogies and demonstrations, you have omitted to explain why you believe this fact doesn't hold for rockets. If Newtonian physics is universal, then rockets must work the way we say. |
18th April 2019, 05:58 AM | #199 |
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Experience is an excellent teacher, but she sends large bills. |
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18th April 2019, 05:59 AM | #200 |
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I am tickled pink I knew the science on this stuff already. I feel almost adult! Almost.
*** Jay, The nozzle part is new to me. As I've always been fascinated by steam engines (the history of changes in stream locomotives is like an object lesson in structured creativity), I was wondering if you know of any other tidbits of still-valid inventions relating to steam? (Apart from it's larger role in deriving the 2nd Law of Thermo.) Thks. ETA: I guess that may be a derail, though. Shucks. For another rainy day, then. |
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