studiot

Because you have done something incorrect? But I see no working to comment on. Of course, the question arises, which mesh current law are you trying to use? There are several versions. Most problems arise when folks try to mix'n'match methods, which you can't do.

Sanity returns to this thread. +1

There are several ways to analyse a catenary So what subject are you studying this in and at what level? There is no hint in your profile other than that your favourite subject is physics. Looking at the picture you posted a snapshot of I don't think it came from a calculus of variations text book. This is quite an advanced way to approaching the problem. Note the calculus of variations is a more advanced technique, not normally taught until well after other forms of calculus have been studied. The standard solution requires only more elementary calculus. Why do you say you are required calculus to solve this? How do you know the curve is a catenary, since the question does not state this and what do you know about this curve? How do you know that RN1 = 3000 since the question does not state that either? If this is a physics problem as it appears have you tried applying the standard conditions of equilibrium to the cable or part of it as a free body?

Note I was talking about siblings supporting each other not the patient. I assumed your question about telling the children concerned the effect on them not the patient. I also assumed that patient as a parent was concerned with the effect on the children.

This is one of those situations that one may theorise about, but act totally differently if one ever gets into that situation. Not having personal experience of this I would offer the following. I would think that a number of children is better than a single child of what ever age, as they would be able to support one and other through whatever is to come in the future, rather than put it all on one child. So treat them as a group, at least with the generalities. Add specifics for the older ones as far as they can handle.

Here is another view of 'curvature'. First consider the usual x,y,z axes for space and then t for time. We expect the numbers along the space (and time) axes to be distributed evenly and regularly. That is we expect them to be linearly distributed. and indeed they are in special relativity, which introduces spacetime. Spacetime is 'flat' which is another way of saying the numbers are distributed evenly and regularly or in a linear fashion. So is ordinary 'space'. Now introduce another entity that has some non linear effect across the axes already defined (ie space, and time) For instance mass. We know one representation of this effect is a force which varies non linearly with the square of the distance. Another interpretation is that the mathematical system of space plus mass exhibits 'curvature', because of the mass. It does not mean there is a further axis in which space 'bends'. The curvature is the nonlinearity coming out when we create mathematical objects (systems) that combine the space and the additional effect eg mass. This is exactly what Mordred posted earlier The non-linearity introduced by adding the density (rho) term to the mathematical system (called a tensor) is reflected in (or develops) a non linearity in the rest of the system, that was linear without it. A tensor is simply a way to collect all (or at least as many as desirable) of the properties of interest into one basket as possible.

Are you sure you mean that and not something quite different? Things are, after all, nouns and do not require causes. I'm not convinced that quantum mechanics requires causes either. It often offers predictions in the form of probabilities. But it does not preclude other forms of analysis that offer different ways of presenting results.

It's a question of understanding, not doubt. So if I understand you correctly you are taking instance of a quake in England & Wales, without further subdivision, and any occurrence of a riot in the same total area. The UK has a substantially diagonally banded geological structure, running SW to NE. So (and I don't know if the were any), a quake in Deal would be linked to a riot in Barrow-in furness if they fell with your selected time frame. Such a link would cut directly across all those diagonals. I don't know if the other diagonal would be more productive. That is a quake in Penzance linking to another Jarrow riot.

Here is a graph of heat capacity up to 1600C, perhaps this is enough?

While you mention ground there was a question backalong about the geographic space compared for the riot and the earthquake. Since neither are points in space their choice is enormously important so can you outline how this was done?

Here you go, some data above 300C it rises dramatically. If you are still interested I will look further.

No one was getting at you personally, but folks who are disappointed when the laws of electricity or other physics don't confrm to their guesswork are going to be doubly disappointed.

Excellent question +1

Hello Alan, I meant to add in tha last post. I hope you take my comments as genuine testing of the methodology, not attempts to discredit the study. The subject is genuinely intriguing.

Conservation laws and system definition can often be tricky. What conservation means for momentum is not necessarily suitable for energy. Consider the following system. You have a totally empty box. (Posh term = control volume) and a source of moving particles of momentum M such that the transit time of one particle through the box is 2 seconds. If t is time then So at t = -1 the total mometum in the box is zero. If at t = 0 a particle enters the box the total momentum in the box at t =1 is M. At t = 2 the total momentum in the box is again zero. So to consider conservation you need to take time into account. Another situation, considering space, this time (pun intended) What is the momentum of a stationary object? So how does conservation apply at a stagnation point in a flowing fluid?

Another methodology query, Alan. I can be reasonably sure that the BGS report of quakes is accurate. For 'riots' I am less sure about the reporting accuracy. Who reported them to whom Who assessed what the definition of a riot is and whether each report met this definition. How confident can you be that before quake when there may have been little to fill the news space riots were not over reported and after a newsworthy event they were not under-reported.T These factors may not account for the near 3:1 ratio you have presented, but have you considered them? Can I commend to you Standard Deviations by Gary Smith? In particular the discovery of the causes of cholera by methods such as you are employing

Whilst I'm not suprised to hear this, I was more interested in its corollary. There should therefore be a lower than average incidence during periods of inclement weather. You often find freak (inclement) weather associated with/following quake activity. This suggests a pattern (to be investigated) quake [math] \to [/math] freak weather [math] \to [/math] increased/decreased riot activity or perhaps all three can stem from a common cause.

Molecules don't 'become hard', whatever that means. Hardness (or softness) is a characteristic of a solid, but it is what is known as a 'bulk property'. You need to distinguish carefully between properties that belong to individual particles and properties that belong to (and only arise with) vast collections of individual particles. Bulk properties arise when particles act together to produce properties they cannot have individually. (Something like that also applies to humans and some animals)

We understand all too well and we really are trying to help So tell us what you mean by 'freeze' If you say turn solid then please explain what you understand a solid to be.

Yay and post it here as well like today's post 42 in this old (2005) thread http://www.scienceforums.net/topic/8139-momentum-vs-work/page-3 Update Thank you to swansont for dealing with this one. The post referred can now be found here; post42 no longer exists as above. http://www.scienceforums.net/topic/94932-necro-hijack-from-momentum-vs-work/

korfezli, you probably won't like this but it needs to be said. It is clear from your answers that you are suffering from some basic and fundamental misunderstandings about the elementary science of matter, whether you call it Chemistry, Physics or Materials Science. Thank you for telling us your objective, that is very useful. Using your imagination to think about what you already know is great and to be encouraged. But it will take you in the wrong direction if you are using the wrong signposts. You need a better understanding of what atoms, molecules states of matter really are, because yours are unfortunately all mixed up. Also you need to be clear about the meaning of 'splitting the atom' No chemical process will accomplish this splitting. Ionisation is not a route to this goal. Splitting the atom means splitting the nucleus, which is an entirely different thing. That results in new atoms that did not exist before the splitting. So listening to John and Sensei (they are experts in this area) will help you correct this and move on. I don't know if they can recommend some source material at the appropriate level for you but get that under your belt and you can carry on dreaming, perhaps successfully next time.

Sure they will. You can contact freeze water vapour to ice or carry out the reverse process sublime ice directly to vapour. But there are no ions involved. Water is a poor example because it does not readily form ions. There are a few, but the concetration is very very low and oxygen forms negative, not positive ions. I'm sure you have a purpose behing the question so why not just explain what you are trying to do? I am going to bed now but Sensei knows a great deal more physics and chemistry than you and will help I'm sure when we know exactly where you are trying to get to.

Once again, how would you do that? You also need to be clear in your own mind what you mean by freezing. The freezing point of sodium chloride is very different from the freezing point of water. If you have sodium ions and chloride ions dissolved in water and freeze the block as Sensei suggested then do you have frozen ions? Or do you have ions trapped in a frozen block of water?

You clearly misunderstood. I asked how to freeze an ion (or ions) without neutralising their charge. So the result is truly frozen ions, neutral atoms or molecules that were once ions. And your link offers me a block of frozen neutral hydrogen.

Just how would you freeze the ion and why would it not regain its neutrality by this process? Of course Sensei's question is relevent. It is all too often forgotten that most ions on our planet are in solution, not wandering around freely since as soon as they hit something they tend to loose their charge.