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A question on Venus
"abc" wrote in message ...
abc wrote: Hi All, Thanks to everybody for your explanations. I was under the wrong assumption that rotation would generate gravitational force while it actually generates centrifugal force. So would it be correct to state that gravity is a direct function of the number of atoms for each chemical element that is contained in a certain volume at a certain temperature in certain spatial (in topological sense) configuration? Are you a lawyer? :-) One of the theorems of newtonian gravitation is that a spherically symmetric body (i.e., each shell of constant radius has uniform density, but density can vary as a function of radius) has a gravitational attraction proportional to its total mass, which acts on point masses outside as if all the mass was concentrated at the center. Non-spherical bodies have more complicated gravitational fields, that have to be calculated from knowing the distribution of mass everywhere in the body. So yes. Temperature has nothing to do with it, other than that T may govern the equation of state that influences density vs radius. Terrestrial planets are a good approximation to spherical symmetry (though not perfect). -- Mike Dworetsky (Remove pants sp*mbl*ck to reply) |
#12
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A question on Venus
In article ,
Mike Dworetsky wrote: One of the theorems of newtonian gravitation is that a spherically symmetric body (i.e., each shell of constant radius has uniform density, but density can vary as a function of radius) If density varies with the radius, then the density isn't uniform.... ;-) -- ---------------------------------------------------------------- Paul Schlyter, Grev Turegatan 40, SE-114 38 Stockholm, SWEDEN e-mail: pausch at stjarnhimlen dot se WWW: http://stjarnhimlen.se/ |
#13
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A question on Venus
"Paul Schlyter" wrote in message
... In article , Mike Dworetsky wrote: One of the theorems of newtonian gravitation is that a spherically symmetric body (i.e., each shell of constant radius has uniform density, but density can vary as a function of radius) If density varies with the radius, then the density isn't uniform.... ;-) -- ---------------------------------------------------------------- Paul Schlyter, Grev Turegatan 40, SE-114 38 Stockholm, SWEDEN e-mail: pausch at stjarnhimlen dot se WWW: http://stjarnhimlen.se/ Better re-read what I wrote. Each shell is symmetric and has a constant density **in the shell**. Ah. I spotted the smiley. -- Mike Dworetsky (Remove pants sp*mbl*ck to reply) |
#14
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A question on Venus
OK ok
This is dumb, as a kid I never thought spinning creates gravity. When you swing anything by a rope around your head it gets pulled out not inward. It has always been clear that mass has gravity no matter how small and that the bigger the mass the more the gravity. Duh no kidding a space station does not have enough mass to hold an ant down. And I have yet to see anyone build a space station that rotates or spins to keep a persons feet on the curved wall. Hehehehe, do they get to have fun and drop the bottom out. I have sat up on those rides, or i mean pulled my knees up and sat with head to center of spin. You have to do it before it gets too fast to pull your body off the wall. But you brought something to mind since I am trying to save a couple million people from asteroid impact effects next month. They claim (though I dont know) that Earth is the only planet that has a magnetic field generated by its iron flow under the mantle. Well its not the spin that keeps Earth away from the sun, its the speed of orbit to keep it in a straight line resisting the pull of gravity. Apparently, some force that we calculate for aphelion and perihelion distances by arc of ellipse is not explaining why anything headed toward a great mass like the sun doesnt pull into the sun but rather increases speed to swing orbit around it. Meteors do not increase speed. What we have in orbit if it increases speed will lose orbit and leave. It must slow down to fall, and then it increases speed when falling but it is not a speed that gains to the extent to regain orbit. Its speed increased toward Earth is not tangent to gravity but rather becoming closer to Earth where even greater speed of orbit would be required. So it crashes if it doesnt burn up from the heat compressed out of air under it. We still have alot of stupid scientists and teachers and planetarium guids who say friction. There is no side friction hot enough or our astronaut re-entries would burn up. It is all about air compression under a falling object squeezing heat out of the compressed air. Do you suppose that since all gravity attracts, and risks deceleration of orbital speed that our wise Creator is using the magnetic field to asist the Earth in being repelled. Does Earth have an opposite magentic field to the sun. Or does the sun not have a magnetic field. Any info on that. Elijah PS. Asteroid impact April 9 will push ocean floors up, melt the mantle under the crust, which spred under continents. With water lost over the land, the ocean becomes lighter and the continents drop under water again as with Noah this time 6000-8000 feet instead of 11,000 due to elevation ratios. Example. Pikes Peak is 8000 feet high resting on 6000 feet. so in 11,000 feet of ocean water it was under 3000 feet of water during the last impact that Noah experienced, while Ararat is 11,000 feet above its 6000 foot plateau and so when under our 11,000 foot ocean it was only 22 feet under surface when the ark grounds on its peak. The fact that Jehovah's witness Angelo Palego found the ark by assuming a drop of ocean by 110 days before it grounded or 74 days before seeing Little Ararat... however he figures it is not mathematical but he came up with an elevation that he found it at and assumes thats where it grounded. That is only coincidence, it gorunded on the peak and whether druing those 74 days or centuires later slid down to its highest position... before other sections slid further... the point is he had Caudio Schranz find it and video it on YouTube (utube) and sadly i would have risked my life over that 6 foot crack to get inside it. I know their are text tablets on it by teh fact the Great Pyramids Holy of Holies and Tabernacle and ark of covenant were all intended for texts, the sarcophagus is symbolic of saving man from death. The pyramids are not tombs. |
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A question on Venus
On Feb 20, 2:07*pm, Sjouke Burry
wrote: abc wrote: Hi All, please forgive me for this question but I am not in the field... Yesterday I learned, to my amazement, that a venusian day is longer than * * *a venusian year as the former is about 240 earth-days and the latter is about 10 earth-days less. Which, if I am not wrong, means that the "sphere" Venus rotates very very slowly. But the size of the planet and its gravity are not that different from Earth's. So my question is how can the planet have that gravity if it rotates so slowly? Shouldn't it be torn apart by the Sun's gravity? Thanks. No... at earth orbit the suns gravity is about .02 G. The ratio of earth orbit versus Venus orbit is 149/108 That makes the suns gravity at the venus orbit about .04 G The only thing unusual you will notice at the surface, is the temperature, 500 degree celcius.- Hide quoted text - - Show quoted text - Why unusual? Consisder the distance from the Sun and the activity of the planet. That's normal |
#16
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A question on Venus
"Elijahovah" wrote in message
... OK ok This is dumb, as a kid I never thought spinning creates gravity. When you swing anything by a rope around your head it gets pulled out not inward. It has always been clear that mass has gravity no matter how small and that the bigger the mass the more the gravity. Duh no kidding a space station does not have enough mass to hold an ant down. And I have yet to see anyone build a space station that rotates or spins to keep a persons feet on the curved wall. Hehehehe, do they get to have fun and drop the bottom out. I have sat up on those rides, or i mean pulled my knees up and sat with head to center of spin. You have to do it before it gets too fast to pull your body off the wall. But you brought something to mind since I am trying to save a couple million people from asteroid impact effects next month. They claim (though I dont know) that Earth is the only planet that has a magnetic field generated by its iron flow under the mantle. Well its not the spin that keeps Earth away from the sun, its the speed of orbit to keep it in a straight line resisting the pull of gravity. Apparently, some force that we calculate for aphelion and perihelion distances by arc of ellipse is not explaining why anything headed toward a great mass like the sun doesnt pull into the sun but rather increases speed to swing orbit around it. Meteors do not increase speed. What we have in orbit if it increases speed will lose orbit and leave. It must slow down to fall, and then it increases speed when falling but it is not a speed that gains to the extent to regain orbit. Its speed increased toward Earth is not tangent to gravity but rather becoming closer to Earth where even greater speed of orbit would be required. So it crashes if it doesnt burn up from the heat compressed out of air under it. We still have alot of stupid scientists and teachers and planetarium guids who say friction. There is no side friction hot enough or our astronaut re-entries would burn up. It is all about air compression under a falling object squeezing heat out of the compressed air. Do you suppose that since all gravity attracts, and risks deceleration of orbital speed that our wise Creator is using the magnetic field to asist the Earth in being repelled. Does Earth have an opposite magentic field to the sun. Or does the sun not have a magnetic field. Any info on that. The Sun has a magnetic field, yes. It isn't relevant to discussions about the Earth's gravity, or Venus' gravity, or the orbit of the Earth. From your post it is obvious that you don't know anything about celestial mechanics or hypersonic aerodynamics. Elijah PS. Asteroid impact April 9 will push ocean floors up, melt the mantle under the crust, which spred under continents. With water lost over the land, the ocean becomes lighter and the continents drop under water again as with Noah this time 6000-8000 feet instead of 11,000 due to elevation ratios. Example. Pikes Peak is 8000 feet high resting on 6000 feet. so in 11,000 feet of ocean water it was under 3000 feet of water during the last impact that Noah experienced, while Ararat is 11,000 feet above its 6000 foot plateau and so when under our 11,000 foot ocean it was only 22 feet under surface when the ark grounds on its peak. The fact that Jehovah's witness Angelo Palego found the ark by assuming a drop of ocean by 110 days before it grounded or 74 days before seeing Little Ararat... however he figures it is not mathematical but he came up with an elevation that he found it at and assumes thats where it grounded. That is only coincidence, it gorunded on the peak and whether druing those 74 days or centuires later slid down to its highest position... before other sections slid further... the point is he had Caudio Schranz find it and video it on YouTube (utube) and sadly i would have risked my life over that 6 foot crack to get inside it. I know their are text tablets on it by teh fact the Great Pyramids Holy of Holies and Tabernacle and ark of covenant were all intended for texts, the sarcophagus is symbolic of saving man from death. The pyramids are not tombs. Aren't you going to feel foolish on April 10th when we wake up and find that none of this has happened? -- Mike Dworetsky (Remove pants sp*mbl*ck to reply) |
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A question on Venus
On Feb 20, 5:41*pm, abc wrote:
So would it be correct to state that gravity is a direct function of the number of atoms for each chemical element that is contained in a certain volume at a certain temperature in certain spatial (in topological sense) configuration? Way too complicated, you don't need to get that complicated. Gravitational force is simply a function of mass and distance. Gravity if proportional to mass, the greater the mass, the greater the gravity. It is also inversely proportional to the square of distance: that means the further you go away from an object, it's force declines by a power of 2 (increase distance by 2 and gravity goes down by 4, increase distance by 3 and gravity declines by 9, increase distance by 4 and gravity declines by 16, etc.). The distance is measured to the centre of the object, not to the surface. The Earth's gravitational force at the surface is at the strength that it is, because when we touch the solid surface, we cannot go any further down. So we're stuck 6400 km/4000 miles from the centre of the Earth where the measure of gravitational distance is taken. If the Earth's surface were closer to its centre, but it had the same amount of mass, then gravity would increase due to the closer distance even though mass hasn't increased. Yousuf Khan |
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