exchemist

Yes I expect most household appliance with an inductive component have a balancing capacitor somewhere, to stop power factors significantly adrift from 1 arising. As you say, I imagine that without it, the extra wattless current could play hell with circuit breakers etc.

Read the effing link, you lazy idiot. It is in layman's terms, with next to no mathematics. If you can't even be bothered to do that, when I've gone to the trouble of not only providing it but directing you to the animation and explaining what it means, you don't deserve any further help. So read the link, look at the animation and then, if there are aspects you still don't understand, ask about them specifically. As for the notion that you can start dissing the science and offering your own theory, when you have shown no capacity to try to learn anything about the topic, what a joke that is. Christ Almighty!

Neuroscience is not part of psychology. Psychology draws on it, certainly, just as it draws on many fields of science. History draws on science too, but that does not make history science. So the fact that psychology uses neuroscience does not ipso facto make it a science. As I understand it there continues to be disagreement about the extent to which psychology can be considered a "hard" science, i.e. one in which reproducible observation of nature (human beings in this case) informs testable hypotheses. A lot of it seems subjective, not surprisingly in view of its object of study and hard, if not impossible, to replicate objectively or test by rigorous statistical trial, as is done in medicine for instance. So when you say it always uses the scientific method for experiments, I would question that. Freud's theories for instance were not arrived at via the scientific method, so far as I know, and to my knowledge there are few, if any, scientifically conducted studies to test them. But it's not my speciality so if you can provide examples I'd be interested.

Thanks, though actually I find @Eise's explanation is the clearer, as he specifically refers to the absence of collisions, which seems to be the key point at issue.

Ah yes, unless there is some means of losing kinetic energy or rather changing their trajectories to heat motion, the particles cannot clump together under gravitation. They whizz past each other and out the other side, and go on doing so indefinitely, like an electron in an s orbital. Neat! But then, how come DM is clumped in galaxies at all? Shouldn’t it be spread even.y throughout the universe?

This raises a point that has only just struck me after reading the Wiki article on rotation curves: DM has to be uniformly distributed across the galaxy to produce the observed rotation curve. But surely, if DM responds to gravitation, surely one would expect its distribution to mirror that of the normal matter, viz. more concentrated in the centre and becoming progressively attenuated towards the periphery? How, then, would one account for its distribution being so different?

At the level of a power network, sure, as the extra wattless current and the associated resistive losses are real enough, even if it transmits no power. But at the level of an individual household, where the inductive loads are, say, a washing machine for an hour or two twice a week, and a fridge compressor from time to time? I doubt it.

But how can that work? If the power factor is less than one, it means there is a component of the current vector normal to the voltage vector. That component constitutes a "wattless currrent", which transmits no energy. So there is nothing to "harvest", surely? It's just out of phase. I confess my scam detector lights up a bit on this topic, as I have seen numerous fraudulent adverts over the years, claiming to gain energy from correcting power factors <1. To my understanding the only advantage of inserting a capacitance to counterbalance the inductance of a motor and bring the power factor closer to unity is that the wattless current does incur resistive losses in the circuit, which wastes some power, though typically not much.

It is explained here: https://en.wikipedia.org/wiki/Galaxy_rotation_curve There is an animation which helps. The left hand galaxy rotates as would be expected on the basis of the mass calculated from the visible stars, while the right is closer to what is actually found. The difference is that in the right hand case extra, invisible, mass is distributed throughout the galaxy from the centre out to the edge. So that's the problem, or one of them. What else could account for the anomalous rotation pattern? There is a hypothesis that perhaps the law of gravitation works somehow differently at very long range from what we see in our own solar system. That is what the article refers to as "Modified Newtonian Dynamics", or MOND. But not many people seem to like that idea very much, as it makes some predictions which are not borne out by observation. The particle physicists on the other hand, struggle to imagine what kind of hitherto undetected particle, or particles, could make up the extra matter with gravitational mass needed to account for the astronomical observations. So we are in a quandary. The hunt is on for mystery particles, while people also struggle to refine MOND in an attempt to overcome some of its shortcomings, i.e. things it predicts we should see but which we don't.

OK, I'm not an astronomer either, so the little I have learned about Dark Matter also comes from magazine articles and the internet. I can summarise what I have learned as follows: - Dark Matter is a just a placeholder label, for something we can't yet explain, - the evidence for it is that the observed rotation rates of galaxies do not fit with the estimates of mass one gets by adding up the visible stars they contain, - there is something going on that seems to cause them to have extra gravitation, presumably extra mass, but which is invisible and transparent to EM radiation. - so the simplest explanation would seem to be that there are forms of matter out there which do not interact with EM radiation, but do exert gravitational attraction. (There are some further cosmological arguments to do with General Relativity and the cosmos but I have not followed those.) Is your understanding the same or different?

Erm, I think his hovercraft may be full of eels.

Is altering the pH of a new, artificially created lake changing the environment, though? Or do you mean digging the lake? People have always built reservoirs.

Indeed, hence the advantage for ships of the crosshead engine, which runs at very low rpm and can have a far longer stroke than a trunk-piston engine. Plenty of time for poor fuel to burn out and able to convert as much expansion into work as possible. Having said that, medium speed engines (400-900 rpm) also run happily on RFO if designed for it, as Wärtsilä in particular has always been keen to point out. They were a medium speed manufacturer for decades, until they bought out Sulzer, the designers of the original RT series, in order to give themselves a stake in the crosshead engine business. (Their big rivals are MAN B&W. Between them these two groups designed 90% of crosshead engines worldwide, at the time I retired in 2011.)

Actually I may be getting out of date, having been out of the business for over a decade now. Take a look at this brochure for Wärtsilä's latest RT Flex: https://cdn.wartsila.com/docs/default-source/Service-catalogue-files/Engine-Services---2-stroke/intelligent-combustion-control.pdf?sfvrsn=6 The graph of Pmax starts at 90bar and goes up to 140! But these turbocharged 2-stroke crosshead engines are really optimised for burning residual fuel oil, with thermal efficiency >50% and, most importantly, where weight is not a constraint. So a bit different from the IC engines the OP has in mind. I remember walking along the upper gangway of a 12 cylinder in-line engine of this type at a power station in Macau, with 4 turbos screaming (ear defenders on), and noticing the individual cylinder heads actually move fractionally up and down with each power stroke. The metal was visibly stretching with each stroke. But these engines had a stroke of ~4 metres and a bore of 90cm, so a stretch of a couple of mm perhaps should not have been a surprise. Running speed was 100 rpm and the generator they drove was like a disc, with poles all around the periphery, to give 50Hz. Pmax has evidently gone up even further since those days.

Yup, a quick internet search reveals pressure graphs with peaks between 30 and 75bar. Latter probably highly turbocharged marine diesels.

Peak pressure of the order of 50bar. BMEP (brake mean effective pressure) of the order of 10bar . I think.

Hmm interesting it can get as high as 8.6. It will be, I imagine, the combination of being fed by water trickling through limestone with a not specially high rate of turnover of the water in the tarn. But indeed I was wondering the same thing: if the pH of the OP's lake is driven by the geology of the catchment area that feeds it, it may a Canutelike exercise trying to reduce it artificially.

Just out of curiosity, do you know what makes the pH in this lake so high? I had no idea natural water could have such a high pH as this.

Yes, but that's the thing with a personality cult. The Great Leader can talk shit and there will be dozens of acolytes on hand to try to divine what he (and it's never a she) really meant. Look at some of the garbage spouted by Mao, which was re-quoted with veneration as if it was pearls of wisdom. My personal favourite from that era was " Cadres, cadres". Nowadays we have "covfefe". * * In my household, covfefe has been adopted as a term for the decaffeinated coffee I drink these days, to manage my tendency to heart arrhythmia.

Arf arf.

Hmm, interesting. It figures, I suppose, in that intermolecular forces will have more effect at lower molecular speeds.

Why have you started arguing with yourself?

That's an interesting subtlety I was unaware of. But it is worth perhaps stressing that there is no difference, in terms of physical state, between vapour so defined and gas.

In this context, vapour steam and gas all mean the same thing. Vapour is probably the best term, and applies to the entire coloured area to the right of the curved line. "Steam" can mean different things to different people, as in popular parlance it can refer to the visible white clouds, which are actually droplets of condensed water, true steam being a colourless vapour. "Vapour" could as you suggest be replaced by "gas", but as water is liquid at STP, vapour seems appropriate. Water "vapour" just means water in the gas phase.

Why was it locked, though? Trying to resurrect a discussion the mods have deemed is finished with or worthless won't be looked on favourably.