studiot

The problem with using water is that the OP has said there is limited time. I expect the resin coating they intend to apply requires a perfectly dry surface to bond to or it will fail. I cannot honestly see the need for the bicarbonate. We used to use sulphuric acid to clean off concrete from tools and it acts very quickly. So quickly that there will be no caustic residue left on the concrete. Any damage will already have been done. I further assume that the grinding is to remove the loose (damaged) material to provide a sound surface for bonding. So once again, why not just grind it out?

No it was not too long, but I'm afraid it did not address my point. I have raised and lowered several bridges in my time and can assure you that your slabs of concrete would not suffer additional compression, merely from raising and lowering. That would require an external agent. I do not know if the Earth pulsates over a long time period or not, so I am genuinely trying to help you make your model work. This is a discussion not an attempt to prove you wrong or right.

So were you able to complete the question? Since the OP has left the scene without further answer and for the benefit of others who might be interested. [math]\frac{1}{{\sqrt 3 + \sqrt 2 }} = \frac{1}{{\sqrt 3 + \sqrt 2 }}*\frac{{\sqrt 3 - \sqrt 2 }}{{\sqrt 3 - \sqrt 2 }}[/math]

I can't find any reference to radar in any of my posts, although I suppose I could design a radar system that interfered with itself, whatever use that might be. Nor did I say that all systems were self referential, just that there was an abundance of such systems to be found in reality. I further tried to offer a wide spread of examples to illustrate the point. My words were particulary specific. I should not need to defend myself against retorts, since all I have done is ask questions. So there should be no retorts, just civil answers, politely put. You are the party making the claims so it is encumbent upon you to substantiate them.

I said nothing about awareness, or self awareness, and I certainly can't find reference to it in your opening post. Strictly, an 'observation' is made when any object, animate or inanimate, interacts with the subject in a way that would not have happened if the subject's actions had not taken place. The subject's actions would include merely the presence of the subject if something different would have happened had the subject not been present. Several posters have tried to explain this to you, so there is no call for the rudeness of your last paragraph. As a matter of interest it is the easiest thing to prove that dualism is an incomplete and therefore inadequate universal philosophy. But that should be the subject of another thread. So I still await a proper discussion concerning my point.

What happens if you bring the square roots to the top of each fraction? Do you know how to do this?

Why can't you just polish the stain out? The concrete will have neutralised any acid. Have you a photo?

I am still waiting for your proof of your claim that you can't be both observer and observed. I also note that several others have offered views on this.

Sauce for the goose..................

First welcome, voultsi, and congratulations on your English. I can just about recognise the Greek letters. There have been huge changes in the career paths for both scientists and engineers over the last 50 years. I expect the next 50 will also see great change. You should only think of doing science or engineering if you really want to, not for the money. The money is poor compared to what a clever person can earn pursuing other careers. Any difference between science and engineering is becoming less. People measuring water quality or air quality are considered applied scientists, not engineers. But really all engineering is just applied science. You may have seen CSI or other forensic science programs on TV. This is a growth area to consider. What interests you finding out or doing and making?

Hello studiot, welcome back to my thread. I will be a more gracious host this time. My apologies again for not responding properly in the past. There was and is no excuse. And I extend this acknowledgment to billiards as well and anyone else who feel I acted improper towards them. My apologies to them also. '''why the crust enters compression when the core shrinks," Well, gravity. Just as the skin of an apple will wrinkle as the surface area of the hypanthium or flesh, to which it is attached, shrinks, the Earth's crust that is much more rigid will in turn begin to respond with similar compressive energies as the gravitational potential energy slowly increases from the inward displacement of the mantle. The only solution to this growing energy level is for the crust to go downward as subduction, or to go upward as mountain structures. Good morning arc, I nearly missed your reply in the flurry of activity after the disappointing closure of the matter continuum thread (not yours). I don't think you quite understood my comment, so I will try to expand. If you inflate a (semi)rigid skinned balloon (eg a metal foil skin) to put the skin into tension. All that happens if you then remove the internal inflating force is that the balloon resumes its former diameter. The skin does not enter compression. At the beginning of the cycles the perimeter 'crust' is neither in compression nor tension. If you stretch a body, and therefore put it into tension, and then release that tension, the bodydoes not automatically enter compression. It simply returns to its unstressed state, unless it has something to convert the strain energy of tension to, in which case can oscillate between tension and compression using the something as an intermediary between tension strain energy and compression strain energy. For example a mass on a spring converts the tension strain energy first to the kinetic energy of motion and then converts that to the strain energy of compression. So it oscillates about its mean unstrained, unstressed, position. To avoid the complication of gravity, that is how a loudspeaker works. Now in your model earth, internal forces stretch the perimeter into tension and then the tension is released by cracking. So there is no strain energy available to convert via an intermediary into compression. You may wish to say that the perimeter is now longer than before, by virtue of the material that has welled up into the cracks and solidified. This this longer perimeter would enter compression if it tried to shrink inwards. If you wish to consider the Earth as a sphere, pulsing in and out of its unstrained radius the very simplest formula for the period of oscillation is [math]T = 2\pi \sqrt {\frac{m}{k}} [/math] Where T is the period, m is the oscillating mass and k is the spring constant. You can estimate the mass of the crust, but what you would do about the spring constant, I don't know.

Three hints in the form of questions At what distance travelled does the block reach its final speed? In what direction do we take the velocity be for the purpose of the equations of motion? Velocity is a vector do we need to resolve it in any particular directions?

This is now the third time I have asked what you mean by a continuum (posts 94 and 108) Were they so impolite you did not deign to answer?

I asked the question because you made the claim that you can't be both observer and observed. But Reality is full to the brim with self referential systems Self replicating autonoma, positive feedback, autocatalysis, self fertile plants, to name but a few. So your claim that this must be so is defeated by counterexample.

Yes you were on the right track apart from then -1.

Why ever not?

Can you show that your algorithm reproduces either the Strapp experiment (with probability) or the Hardy experiment (without probability) ?

It sort of reminds of the the heyday of the oil industry when visiting Arab dignitaries would buy a roller ( + driver) to taxi them from Harrods to Heathrow and then hand the keys to the driver "It's yours" as they departed.

The trouble with 'homework help' is that it does not tell us what subject the question is in or at what level. So is this geography, politics, an English essay, general science or what, and at what level? Help us to help you.

The Moon's relationship to the Earth is not stable. American measurements of the last thre decades or so show that it is receding at 33 mm per year. https://solarsystem.nasa.gov/planets/profile.cfm?Object=Moon&Display=FAQ#q17

The mechanism proposed in post#349 does not explain why the crust enters compression when the core shrinks, unless the crust started the cycle in compression, which was not stated.

I really don't know what this thread is about, but would like to pitch in with a couple of observations, apologies if they are irrelevant. Firstly it doesn't matter much to us how much the Sun puts out since most of that flows the other way. What matters to us is how much we receive. And that bring me to my second point that picks up on some of your comments. What we do receive is very unevenly distributed over the planet's surface. Significant natural processes occur transporting huge quantities energy about the surface of the planet. Most of this transport is actually carried by mass in the two fluid environments. Understanding and allowing for this transport is vital to any discussion of climate and climate trends, but is sadly all too often forgotten or ignored in discussions.

OK, my post showed how to get your first highlighted (in yellow) questions ie the negative delta H double double star and T in the denominator. It's to late to assemble the rest of the derivation tonight, I will see what i can post tomorrow, if no one else does it first. It would be very helpful if you would label your notation, since everyone has a different notation for this. Particularly with the rate and equilibrium constants. I assume you have realised I can't do double daggers and have used double stars instead. Edit, Do you realise you have incorrectly multiplied equation 1 through by -1 to form equation 2 incorrectly? [math]\Delta H - T\Delta S = - RT\ln (K)[/math] [math] - \Delta H + T\Delta S = + RT\ln (K)[/math]

Actually the real moneyspinner business is providing diggers for placement in London basements.

I think the news article (there were several if you Google) states not that it can't be done but that its costs more to lift the digger out than to buy a new one.