studiot

I don't suppose any of the current tory tinyminds in the leadership race will do anything about this scandal or if the even know or care about it. https://www.bbc.co.uk/news/uk-england-manchester-62494987

Seems rather less primitive than I was thinking. Surely you can only establish a connection if you can 'distinguish' the two elements ? And many so called basic operations such as counting can be mimiced by not counting at all but simply placing in one to one correspondence.

Thank you for taking my thoughts seriously, even though you disagree. +1 You make a very clear point. Nature of does something mor or different from our predictions. But not always and averages have a way of reasserting themselves especially over the longer term. Some comments I used the USA recent natural occurrences as an example, there are plenty more around the globe. I am disappointed no one has taken up my comments about the Indus and the Harappans. With specific reference to the UK, we are now moving into a patchwork of water restrictions we should not have. Unfortunately the politics is that we now have a patchwork of relatively small water commercial companies that are now largely owned by foreigners. This was due to the privitisation and fragmentation of the water industry that was gradually drawing together over the first 3/4 of the 20th century. We were told that privatisation was 'good because it would bring private investment' but, of course, that never happened. Companies, espcially foreign ones, are there to take money out, not to put it in. All they do is 'manage existing installations, some a hundred or more years old or more. There was considerably greater vision 150 years ago. Further there is a general lack of cooperation between the companies and between the companies and the general public, who rightly mistrust them. There are bright spots in this but they are few and far between. We also have a 'regulator' who finds is easier and more convenient to regulate the customers, rather than the suppliers. Because another 'obvious' engineering solution is to simply restrict customers access to supply. As a small country, with plenty more water than we need, and a substantailly reducing industrial demand following the demise of much of UK industry; We simply should not have a general flood and drought problem, though as you say Nature will still occasionally thwart us. The sort of (natural) drought we are now facing last occured in 1976 - almost half a century ago.

I like it. +1 But correspondence is more primitive than counting - which requires numbers. Consider the following. The Australian Aborigenes had a number system one, two, many. 3 numbers only. So they could distinguish but not count. Marked tally bones (there may have been tally sticks as well but these will not have lasted as well as bones) for 30,000 - 50,000 years ago have been found. What were they for ? Well perhaps the head of the tribe sent scouts out to mark a tally stick by scoring marks onto the tally in one-to-one correspondence with either goats they were herding or hunting or the war aprty from another tribe or whatever. Perhaps the headman could count but the scouts ? A matter of conjectures. These marks predate known cave writing, though not pictures. So the scouts were distinguishing and tallying. Mathematics is about a whole lot more than machine calculation and numbers, geometry for instance. How would your machine tell the diffeence between a square and a rectangle or discuss the symmetries of a snowflake ?

So you can't do mathematics without a CPU ? Thanks for the clarification. I still think that is too high a level of operation. Inow has a similar idea to mine, with 'division'. Mibne is still more basic though. The two most basic operations in maths I can think of are are 1) Distinguishing between two 'objects', say A and B. 2) Putting 'objects' into correspondence with each other. These two operations may have also been the start of language as well as mathematics. All the proposed operations above (by others) rest on these two but may be that someone can think of some more. This is a genuine discussion topic folks.

So how would you establish the equivalence relations greater than and less than in this system ?

Since I don't understand what you mean, I can't answer the question. But I don't doubt you will have a worthwhile opinion on the OP, when you explain.

The title says it all. What operations do you need to carry out before you can do any sort of mathematics ?

Speak for yourself and the handful of other like minded people. The rest of the seven and three-quarter billion people on the planet have more pressing concerns.

Yes martensitic stainles steels are usually magnetic, other types less so because they are usually low carbon and softer. High carbon martensitic stainless steel is high tensile, brittle and can take a keen edge. Normal stainless steel is of lower tensile strength and softer (more ductile) unless there are additional alloying elements such as molybdenum or manganese. The stainless part comes from having sufficient nickel and chrome in the alloy. But whilst chrome-moly alloy steels can be used for springs, they are often chrome-vanadium, with even some cobalt and or copper. https://www.coilingtech.com/chrome-vanadium-springs/

I think joigus has your answer but I would like to elaborate a bit further. It's very often the external pressure that counts, especially in chemcial reactions since the reactants in the open test tube are pushing against the armousphere, which is sensible at constant pressure. So this will be PV work done by the system on the surroundings. As joigus notes the internal pressure of the system is not measurable. Thermodynamics (first law) is about the energies and masses crossing the system boundary and you will often find the calculation easier on one side or the other of this boundary. Finally this is for irreversible work. A reversible change would be carried out so slowly that the internal pressure always has time to equilibrate at each infinitesimal expansion or contraction.

You have posted this in homework help. Are you working on some kind of project ? If so here are some more pointers. Babbage's wife, Ada Lovelace probably added more to computer theory than Babbage himself. But the great thing would be to separate the those who added practicality and those who developed theory. Both of these were needed in roughly equal parts. It is not known who invented the abacus, various civilisations in ancient history had some form or other. Later calculating machines were developed to, well to help calculate values for tables. Napier was the theorist and Outred the practical implementer (he invented the slide rule) Digital Theory probably started with DeMorgan. This is where Babbage came in with his analytical engine (the practical man) and Ada was the theorist. The next big development came before Turing's time and was still purely mechanical. Industry threw up the need for control of machines that required a series of steps. Hollerith invented the punch card system, which also started 'data processing'. Electricity was also beginning to make an impact and devices using electric switches (relays) followed by vlaves (american tubes) and then semiconductor devices were made. Von Neuman formalised the idea of 'the stored program architecture' originally using Hollerith cards and the modern computer was born. Turing did much theoretical work on the capabilities and limitations of such machines and invented the 'turing machine' as an idealised model. Now I have started your rehabilitation from the red marks with a +1 since you are showing some sense now. Keep it up and I hope you project, if you have one, goes well.

This should help. Exactly. That is what Erina quoted from Tesla So charging efficiency. I have attached two diagrams firstly the charging diagram of an ordinary common or garden 12 volt car battery. As can be seen the charger or alternator produces a (laughingly) constant voltage and the current is initially high for a discharged battery but gradually drops off as the battery voltage rises so the difference between the charging voltage and the battery voltage falls until the charger is just receiving a 'trickle charge'. This trickle charge can safely go on indefinitely. Processes within the battery dissipate the very small amount of energy safely as heat. Also since the charger voltage is only just higher than the battery voltage it cannot add further charge to the battery. Also shown is the dashed constant current line that sophisticated battery 'fast' chargers operate. It is not safe to try to pump the high initial charging current into the battery so when the finish point is reached this type of charger switches itself of and perhaps disconnects the battery. Lithium ion batteries can also be charged in this manner but constant voltage charging is slow especially when the amount of charge to be added is considered. So they use constant current charging and sophisticated controls which stop the process at the point A on the curve. Now an EV battery is much higher voltage than the old type - the Kia is over 300 volts - so the safety implications of overcharging are much more serious. Also there will be statistical variation in the absolute capacity from battery to battery. So the manufacturer rates the battery below this point and I have shown the statistical safety margin above this on the curve. But note the curve also turns over compared to a straight line 100% efficient charging, just as the 12 volt battery did. I have also drawn line BC to show this 100% efficient charging line. Now the further up the curve you go the further below 100% is the charging efficiency. So where the manufacturer places their battery rating on the curve determines the charging efficiency. The Kia is a cheaper car than the Tesla so I expect that they can less afford to offer a generous rating and are pushing their batteries harder. This would imply that their charging efficiency suffers comapred to the Tesla.

You have a PM. Carbon dioxide concentration is fourth on the Cambridge list of 24 atmospheric gases and particulates and stood at 384 ppm in 2007 with an annual increase over the previous decade of 1.65 ppm. Ther primar source (referenced) was NOAA. So something over 400 is hardly suprising today.

I'm sorry I still don't understand this. A formula is not a number. Perhaps there is some translation problem ?

What a silly question and what a good reply from @Peterkin +1 The question is like asking which goes faster a Fiat 500 or a Trabant , whilst ignoring the likes of Porsche, Ferrari, TransAm etc. What do you mean by computer anyway ? The object that most people identify with as a 'computer' was due to Von Neumann.

I didn't say it was all clouds and I didn't say that water vapour did not act as a greenhouse gas. In fact if your read carefully I said the opposite. Which is why I said

I can see I'm wasting my time here. What are clouds, if not water in the atmousphere ? Perhaps you get clouds inside the coal in a coal mine ?

I don't want to be nit picky. Especially as I sometimes use the analogy of eddies in a stream to discuss the idea of a semi permanent structural feature in a stream to represent what is meant by the quantum idea of particles being just such structures in quantum fields. But here we are discussing classicla EM fields as far as I know. So a few comments on the text. The electric field E has zero curl, it is the magnetic field that has non zero curl. epsilon and mu are not scalar constants , except in special circumstances, actually they are second order tensors that interact with the E and D and B and H fields which may result in these not pointing in common directions. The energy density is one half E cross D and one half B cross H for the electric and magnetic fields respectively.

I am not minded to say much about atmospheric water since nobody is very interested but the offered analyses do not hold water (pun noted). The wavelengths that different gasses operate on for radiative absorbtion and emission effects differ from gas to gas. But atmospheric water has a net cooling effect on the Earth. Not only that but the effects depend upon the position (altitude) of that water. Here is a short extract from a 2018 New Scientist article about the subject ans what different experts around the globe from Canada to the US to New Zealand to the UK are trying to do about it. +1 to phi for his note on the polluting effects of nitrogen oxides.

Consider this oh monger of doom and gloom: The polio vaccine took 20 - 25 years to develop. The covid vaccine took substantially less than a year. Edit On the lighter note of "what do aliens do ?" Read "How to be an Alien" by Georges Mikes.

Thanks to swansont, +1, for pointing out the long term and statistical nature of the rotation. Statistical fluctuations are, by definition, 'unexpected' in any specific fluctuation timing or quantity.

I have a lot of data, too much to scan and post as such. But if you can indicate where you want to go with this I can certainly condense it for you.

I'm sorry I don't understand this comment. Heat is not necessarily a bad thing. The capacity of an electric vehicle battery decreases markedly with lowering of temperature, (or raising it above optimum which is in the 20oC to 23oC range) The car manufacturer will specify the capacity at this temperature. At 5oC the capacity will be 25% - 30 % lower and it can be as little as 50% lower in freezing conditions. Also the capacity depends upon the equipment used to charge the battery. The Kia Nero has a 64kW-hr rated battery. But it needs a 3 phase supply to achieve this capacity. Ordinary UK mains can only reach 80% of this value ie 51 kW-hrs, I recently charged a Kia from completely flat to this level - It took 28 hours charging at 10 amps on the UK 240 volt mains. This equates to 67 kW-hrs. So the charging efficiency was 51/67 x 100 = 76% Other types of lithium-ion (there are several types) batteries have different characteristics.

OK so the Telegraph has done its job as a respectable paper pretty well. These figures concur with other sources I have. In particular my Cambridge Handbook of Earth Science Data (mine is the first ed 2009), which gives all sorts of tables of useful data on - well Earth Science In the chapter on the atmousphere it lists much more comprehensive composition data, including non gaseous components such as dust and volcanic input. It also references other reputable sources such as NOAA, The UK Met Ofice, standard texbooks on Geochemistry, Chemistry and Physics. Amongst many other data tables, it offers a table of of the energy fluxes between the Earth and its atmousphere that may be a useful addition to your Telegraph data. Just a small point about you Telegraph data. The difficulty with the halocarbons is not the greenhouse effect, but their chemical action high in the atmousphere to deplete the ozone layer which proctects us from harmful high energy solar radiation.