studiot

One factor not yet considered here is the age of the car. Electric cars have only really started selling in volume about 2 years ago. Before that it was only specialist and nich market stuff. In order to grow their market volume ev manufactures have been offerening discount insurance to buyers of their new vehicles. A couple of years on and those owners now looking around for a better deal may well have a shock. As a matter of interest Kia include a 5 year repair deal so the sot of parts may not be such as factor, They also claim that their own insurance prices for IC and EV vehicles are very similar.

Good morning Julius and welcome. I see that the response to your question so far has been rather cool. Perhaps you are a youngster just beginning to think about such things, perhaps you are older and still thinking about such things. Either way thinking is good. So don't be put off by the adverse replies the members are only trying to help. One way to think about this is to regard time as what mathematicians call a functional parameter. When we have several independent variables a parameter is a single variable that allows us to tie them all together by means of some formula (or function) between the parameter and each variable. The Universe is Space which has 3 dimensions. That means that we need three independant variables to refer to any part of that space, usually x,y and z. Time can then be considered as a parameter that specifies where in Space an event occurs, by means of some formula such that x, y and z are individual functions of the t parameter. Time is so useful as a parameter that the symbol for a parameter is usually t. Here is a simpler example in 2 dimensions. The standard equations for a parabola are a = at2 ; y = 2at. Ask if you want more detail or dicussion. Be warned also that as an anti spam measure new members are only allowed 5 posts in their first 24 hours. Afer that it is unlimited so long sas you are reasonable in what you post.

It seems to me that that this question might be resolvable depending upon the response of an AI to something it has not been taught. For example I don't believe a human would have much trouble understanding this One of the earlist proposed uses for AI is as a robot driver. So what would such a driver's response be to the following

So just exactly how common is it with references. I would suggest distinguishing between how common in settled communities, like say Denmark and war zones like the setting for your video. But fundamentally people need to take more responsibility for and care their own actions. How does the frequency of this type of misadventure compare with say the frequency of an ordinary joe clearing the rubbish bins or alleys and receiving an unwanted 'needlestick injury' ?

You have omitted one of the dimensions of energy. Actually one thing Markus has not stressed is that Using coordinates directly does not satisfy the Principle of Relativity. You need to use coordinate differences for that. It is also worth realising that n dimensional coordinate rquire n+1 pieces of information (unlike geodesics for instance ) I totallty agree. Relativity cannot cope with singularities. It is interesting to note that, as you say, such singularities arise in Fluid Mechanics and Nature has its own resolution, not predicted in the mathematics on eithe side of a singularity. Shock waves and the Hydraulic jump are specific real world examples, and energy is involved in the analysis.

Item on today's News (quizz) On account of the extensive space junk layer about the Earth, only 37% of prayers are now getting through.

Still waiting for your reply. I feel like the pupil who carved onto a desk in my school In Honour of those who died waiting for the bell

I can't imagine the subject which offers these examples as risk assessments. I agree that the examples you quote are a long way from what I understand by the risk assessment process. There are several different forms of risk assessment, depending upon the intended purpose of the assessment. But all depend upon identifying all the risks and assigning a probability to each one as well as a second parameter known as the severity. Roughly this means the cost of being wrong. Formally it says that given the event at risk actually happens, what would be the consequences - would it actually matter ? The implementation then becomes a matter of the statistics of conditional probability. Finally an assessment of reducing or removing the identified risks is often appended at the end, particularly in Health and Safety matters. Here are some examples Compare the risk assessment for a Nurse and a Seamstress pricking themselves with a needle. 1) A seamstress gives herself a slight prick with a sewing needle. Assessment There may be some short term pain but it is a common occurrence usually resulting in no harm. Possible solution Use a thimble. 2) A nurse pricks slips and pricks herself with a hypodermic needle she has just used to inject a patient. Assessment Risk transferring to herself a dangerous drug or dangerous disease(from the patient) such as HIV or Hepatitis. Consequences can be severe - death or serious injury. Possible solution Use an automatic self retracting injection device. A second place formal risk assment appears is in engineering in what is known as Limit State Design. Here the objective is to produce a known and acceptably low probability of failure of an engineering design by statistically combining what are known as partial safety factors. So tell us what the actual question is that you have been set, for more help, since this is Homework.

something like this is used in engineering, including computer engineering. They are called heat pipes. https://en.wikipedia.org/wiki/Heat_pipe

Sure. But beware og these EVs https://www.bbc.co.uk/news/uk-scotland-67005620

Did you miss my last post ? The Uk electricity supply is 230 volts at 13 amps single phase from a single domestic socket. That gives you 3kVA. More power can be had by using a dedicated 30 amp supply, still at 230 volts. That is equivalent to one ring main direct wiring from a single fuseway in the box. This is nearly 7.5 kVA and is used for say 8 kVA instantaneous showers. However the charging lead for my brother's car, like most uk electric vehicles limit the input current to 10 amps at 230 volts. So your neighbour has 9 kVA in good daylight. Jolly good if he is a night worker and charges hois car in the day otherwise he would have to layout for storage capacity equal to a day's charge, if he wanted to work in the day and sleep at night. say anothe £15000 on top of the panels and vehicle. In which case the EV would be more efficient, if you returned to base between trips. My other brother is on his second hybrid with a 25 - 30 mile range and does mostly short local trips like you do. Mainly the batery allows the vehicle to half its fuel consumption or double the miles per litre. This is again competitive with all electric. Some thread back I published an efficiency graph for an EV battery, here at SF. Their optimum temperature is 23oC, although the fall off is much less severe at higher temperatures it is still less efficinet at 30 than 23.

I see no response to my comments. How Christian is that ?

So your question has nothing to do with golliwogs per square root of carrot or any other strange measurement unit. Unfortunately real life is more complicated than your wish, especially as no one yet knows the 'carbon cost' of electric vehicles, which must vary according to your source of electricity. Here are some real world figures from England. Petrol My car does approximately 9.3 miles per litre, pretty reliably since I do very few journeys of less than 10 miles. Petrol in Bristol and Plymouth are usually about £0.1 per litre more expensive than where I live, so I prefer to fill up near home. My tank holds about 35 litres which give me a range of 325 miles. Electricity My brother's car does about 4.3 miles per kWH but that can decrease by 50 % in worst driving conditions (winter, very wet, night time) It should be remembered that all the auxiliary machinery in an electric car (heater, wipers, lights etc) are run from the battery which is the only energy source. Now here comes the awkward bit. When my brother visits he pay me £0.3 per kWH to plug into my english mains and recharge. His car has a capacity of 64kWH but this can only be achieved with heavy duty 3 phase industrial supplies. Lesser supplies can only charge up to 80% that is 51 kWH. The commercial cost of electricity varies from £about £0.5 to £0.8 per kWH. but only the most expensive will achieve a recharge time of 30 mimnutes (as compared to 3 minutes for filling my car). Further my brothers car currently attract zero road fund licence (tax) compared to my several hundred pounds. Also petrol is heavily taxed in England, far more so than elctricity. Heaven only knows what it will cost to run an electric car taxwise when the chancellor has forced everyone into them. My mains supply takes over 24 hours to fully recharge his car from flat. So there you have it. Some facts and fiures from the last 3 years driving experience.

I didn't say it did. But I also indicated that clearing up the OP misunderstandings about units in general would help bring clarity to the question.

I do this all the time with both my own petrol car and my brother's all electric car. Simple question How many litres of petrol or Kwh of electricity do I need to tget to Bristol / Plymouth and back ? Really I want to know whether to top up before I go or not. So yes please @Arthur Smith What are you actually trying to do - The answer is unclear to me. Not so because this is incorrect maths .

I have had little time to follow this squabble but several things are unclear in your OP. Firstly what do you want sulphuric acid for ? In other words, how much and how pure ? The stuff is produced and used in large quantities in most developed countries and readily available, suitably prepped for purpose. The scale of the enterprise is such that it will never be economically viable to produce your own. But then you may not want to actually perform the synthesis, you may just want to discuss how to do it from different starting materials. Over to you to enlighten us so that the best help might be offered.

Perhaps, but nevertheless the summary is good and perhaps useful to the OP as I said. Furthermore if it is genuinely the output of an AI, known to be unreliable, then confirmation of its worth from a unreliable greybeard human may also be welcome. 😀

I think that Laplace's great insight was to realise that action-at-a-distance is not the same as instantaneous. Also to be considered is the fact that the universe is an Earnshaw system. (1842 again after the death of Laplace but before Faraday introduced any sort of field, near or far.)

Whilst there is some truth in both statements in this exchange I do not think this does justice to either Newton or Laplace. In fact from Newton onwards the problem of 'Action at a distance' was known about and considered by many scholars up to and beyond Einstein, That is for at least four centuries from 1650. Laplace did indeed consider the possibility of a finite speed for gravity, amongst other possibilities available at the time. But he did not prove anything about it. In fact, unfortunately both he and Newton were misled by erroneous observations by Halley. Generally the problem was considered too dificult and kicked into the long grass Both Newton and Laplace were dead before Faraday proposed the first real field theory. A good, not too long, best current evaluation of who did what when up to the present day can be found at https://www.mathpages.com/home/kmath690/kmath690.htm

That wasn't what you said, literally and does not follow either. Why do most folks go for plain featurelees barren white walls and ceilings, by design ? It is true that a barren featureless universe could be a characteristic of a no design universe, but it could also be a feature that a designer wanted. Such dual purpose characterisitcs are of little use distinguishing. What is needed is a characteristic that can only derive from either lack of or priduction by design activity. The OP is looking for the former, but I agree that is no easier than the latter. Thank you whoever liked my last post.

+1 @Brainee This is a nice summary, I hope you will look at it.

Would this be your point ? Because if so how do you account for the intricate patterns that arise quite naturally in Nature, without any intelligent design whatsoever? I agree that at one time some of these were afforded mystical significance, but only cranks do that today.

I hope so. Thanks for the info +1

Exactly so, except you didn't originally specify a minimising geodesic. But even then you must be careful since the ame piece of geodesic can be minimising or maximising depending upon the final endpoints. For instance London, Brighton, the North nd South Poles are all on the Greenwich Meridian, which is a geodesic. But is it minimising or maximising ? Well if I start from Greenwich and travel south I am travelling along a minimising geodesic, But if I am going to the North Pole it is a maximising geodesic !

Yes, you are correct. I confused myself there. I understand the sectional geometry given in your Fig1, along with the necessary exaggerations for clarity, though I welcome your later additions to improve communications. In particular your article should start by saying a nucleus is at the centre of your donut. But as far as I can see the choice of alpha and gamma are arbitrary so you should make clear at the outset how you have divided up the fixed Bohr radius. I asked you " orbiting what ?" and you have now added a nucleus for the first time. Thank you. But what happens if there is no nucleus or the nucleus is from another atom, say He+ or Li++ ir Be+++ ? The energy level depends upon the square of the atomic number and the Bohr radius is define for one electron systems. How does this affect you numerical coincidences for these and all the other atoms, since their ground state radii will be different? I also asked you what was orbiting and you have simply called it a quantum, which is a poor nomination since a quantum is not necessarily small but should be a very specifically defined amount of something, which you have not provided. This is a crucial question because of the Physics. If this something has mass the question of its speed immediately becomes important since its mass appears in the physical equations. If you are thinking of the model with a photon travelling at the speed of light, then the problem becomes Can then electrons exist without an associated nucleus to produce this toroid and helix ? I ask this because I can easily produce a beam of electrons free of any nucleus. so how can an electron be a photon trapped in a toroid ?