pavelcherepan

300 million kilometers = 300 billion meters = 300*10^9 = 3*10^11 Makes sense? Are your calculations correct or not?

Robittybob, why are you starting the same kind of discussion as the one you already have? The original question is about gravitational attraction so let's not stray away from subject, shall we? Does this look familiar? [latex]F_g = G \frac {Mm}{r^2} [/latex] Something's wrong with my LaTex skills. At L3 you get 13.34*1015 Newtons roughly.

1. Check your numbers. You have done an arithmetic error in Excel. For example at L3 [latex] v_e = \sqrt \frac {2GM}{r} = \sqrt \frac {2*6.67*10^{-11}*6*10^{24}}{3*10^{11}} = \sqrt \frac {80.04*10^{13}}{3*10^{11}} = \sqrt {26.68*10^2}= 51.65 \, m/s[/latex] The rest of your numbers have the same error. 2. Explain physical reason for subtracting square roots of escape velocities at different distances? Can you show me where you got that formula from or explain what it's used for? 3. Have you invented the term "Terminal Impact velocity"?

I'll 're-check your calculations when I get back to my laptop but they don't seem right. At 150 or 300 million kilometers from Earth escape velocities can't be in order of kilometers per second, it's some meters per second. You've lost some zeros so it seems

"Later, with Nicholas Metropolis, he assisted in establishing the system for using IBM punched cards for computation." In my mind that is an automated and programmable computation method and no one said there were digital electronics, that's just another of your straw men.

Can you show me the formula you used for these calculations?

Ok, enrichment was done in multiple places, because different methods of enrichment were tested and not for security reasons. Also, Dr.Richard Feynman who was on fact in charge of the group that was responsible for all calculations distinctly remembers computers. "No modern tooling" - yes the a-bomb was done with hammers and bigger hammers

Ok, MigL, I understand where you're coming from but let's imagine we throw one ball high enough that it reaches the orbit of the Moon and the second one - 10000 kilometers higher and then start falling down. How big would be the difference in velocity then? Secondly, we weren't talking about starting at 0 because initially we were playing from a paper that described collision simulation and there the initial speed is estimated at 4 km/s. Wikipedia article has the same estimate. Now how much change due to Earth's gravitational influence (percentage) with initial velocity of 4 km/s and starting points at 150 and 300 million kilometers away? The difference in escape velocities ( relative to Earth) between these points are some 100 m/s.

Look at this. You've already solved everything. The last step left is to put = sign between left and right sides and find x. To make it easier use studiot's advice and multiply both sides by a 100. Nitrogen doesn't participate in the reaction so you can forget about it for now.

Well done. So CO here is not very stable in normal conditions so as soon as there was a chance it grabbed an oxygen atom from the air and got reduced to stable CO2.

Now try and count oxygens on both sides of the equation. Are they the same? Another question - how do you reckon CO became CO2?

Can you see that first term on the left is CO and on the right - CO2? And all other reagents are the same.

Newton's laws fail to predict properly when velocities are a appreciable fraction of c, that's why it's been largely superseeded by Special relativity.

Yes, both Newton's laws and Stefan-Boltzman laws are approximations. Doesn't matter if they are called laws, those are still theories. The meaning of "law" is different in science compared to justice.

Actually dissolution of crystallic salts is an endothermic process. You need to supply energy to break crystal structure as ions dissolved in liquid have higher entropy than in the form of crystal lattice. On the other hand crystallisation is an exothermic process and you can possibly get energy that way, although I haven't seen any such designs. <Thermodynamic view on crystallisation> EDIT: Come to think of it, difference in salinity changes water density and that's the leading cause for Gulf Stream, so it's possible to get energy from water flows due to difference in salinity, but I'm not sure if you'd get a net energy gain.

Good. Problem solved

Then we should dump nutrients in the seas

You said "You could have convinced yourself that planets further apart will collide at a higher impact speed." to which I replied that I haven't, which means that I haven't convinced myself. Your question was also very unclear, for example, why would I have to convince myself? That doesn't make much sense. But anyway, I'll be waiting for your calculations.

Nope. I haven't.

But is there really much point? I mean, chlorophyll is not the only participant of photosynthesis and plus if you just dump plenty of it in the seas without biological assistance it won't be re-created. I reckon it's better to artificially grow lots of phytoplankton and dump it around. That should work better.

Harold, the discussion was about nitrogen, wasn't it? By the way, the discussion point has ceased and the OP hasn't been online since October 2014, so if you want to discuss this topic it's better to create a new thread.

The fact that density appears to be infinite is just the sign that it's the extent to which General Relativity is applicable. Obviously, as you correctly pointed out the density can't be infinite as it would imply infinite mass which is not true. So there is something we don't understand, maybe it will be solved with Quantum Gravity, maybe M-theory, but definitely some update to out theories is needed. On the side note - there is a theoretical description of the black hole in superstring theory that doesn't feature singularities. See <Fuzzball>.

Calculation for what?

But what's the point in such a calculation? This is for an object moving in the atmosphere. How long before the impact would Theia move through the atmosphere? Couple seconds? At that velocity atmosphere wouldn't be able to slow it down appreciably. OK, let's do calculations based on current atmospheric characteristics, because I have no idea what the density of atmosphere was back then: [latex]V_t = \sqrt{ \frac {2mg}{\rho AC_d}} = \sqrt{ \frac {2*6.39*10^{23}*9}{1.204* \left( 3.39*10^6 \right) ^2*3.14*0.47}} = 0.25*10^8 \,m/s [/latex] Where I used current atmospheric density at surface of 1.2041, mass and radius of Mars and drag coefficient of sphere (0.47) and a lower g value of ~9 m/s2 So the terminal velocity, if you're really wondering about it, is higher than the speed of light about 250 kilometers per second. Just as I said, atmosphere is not capable of slowing down such a massive body appreciably. EDIT: Corrected a lame error in the calculation.

No, MigL, you're very much welcome and maybe you'll help clear the misunderstanding we're having I figured that what he really wanted to know was the impact velocity, because the term <Terminal velocity> is hardly even applicable in this situation? And the impact velocity would really (based on what I know) depend on excess velocity and strength of gravity field so I've done calculations for the Earth of 75% current mass and smaller radius. Maybe you know of the other way that can be done?