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Does lightning actually always come from the ground?
And which stream of ground lightning is the positive, the one that leaves the ground or the one that leaves the sky ?
Both streams the leader and tail both emit light, are they both not a positive?
Quote from: jccc on 18/03/2015 17:13:55what is energy level? are you sure there is such thing? do you have the mechanism? Dear jcccCan I suggest you take the cover off your computer, take a hammer and chisel, pride apart the main processor and count the number of 0s and 1s you can see.Children, don't try this at home!
what is energy level? are you sure there is such thing? do you have the mechanism?
Quote from: Thebox on 17/03/2015 23:41:33What makes lightning?There's a fair bit of poppcock in the replies above, and not a lot of physics. Perhaps you'd care to rephrase the question: are you interested in how clouds acquire an electric charge, how the lightning discharge initiates, or why we see it?
What makes lightning?
Quote from: alancalverd on 18/03/2015 18:36:34Quote from: Thebox on 17/03/2015 23:41:33What makes lightning?There's a fair bit of poppcock in the replies above, and not a lot of physics. Perhaps you'd care to rephrase the question: are you interested in how clouds acquire an electric charge, how the lightning discharge initiates, or why we see it?Alan, the specific question I was trying to answer with my piece of poppycock......
Lightning isn't light - that may be the cause of your confusion. What you see is the light emitted by the hot plasma formed when an electrical current flows through the air. Negative and positive refer to the electrostatic charges of the two objects (usually cloud and ground respectively) between which the discharge current flows.The ground "streamer" is again the light emitted by the hot plasma at the start of the discharge. It is as likely that the discharge will initiate from the ground as from the cloud - in fact probably more likely as there are sharp features on the ground and the electric field gradient around a charged object is greatest where the radius of curvature is least.Whilst the ground streamer usually has a distinct origin, there probably isn't a definite "point zero" in the cloud - several discharge paths may begin but they usually coalsece into a single apparent origin where the current density is sufficient to produce a hot plasma.
Why "say the ground is negative" if it's actually positive, as you can see from the streamer charge, and as I said in my explanation? "What goes up" is then positive charge, and "what comes down" is negative charge. The (mostly neutral) air in between just gets cooked because it's in the way.
A firstly unseen action, and when the cloud can not absorb any more energy the cloud surges and sends back through itself of an unseen stream, a backwards surge giving the effect of seen lightning?
If you could have a mass of solely negative charge, and surrounding that mass was a positive charged atmosphere, the positive charge would do its best to centripetal find and attract to the center of mass of the negative object where the object is it's most density?
Quote from: alancalverd on 19/03/2015 06:35:42Why "say the ground is negative" if it's actually positive, as you can see from the streamer charge, and as I said in my explanation? "What goes up" is then positive charge, and "what comes down" is negative charge. The (mostly neutral) air in between just gets cooked because it's in the way.What comes down is the same has what goes up, neither can be negative?
I get the cloud is a negative mass, that extracts a positive from the air , the ground and also the sun.
I am going fishing soon for 24 hrs so it i will be friday night before I respond.
I am interested in.. how the lightning discharge initiates, the initial point in a cloud where lightning starts its short journey.
a cluster of positive charged particles, the cluster particles would want to repel each other
Centripetal
What goes up and what comes down is the same stuff right?
Quote from: TheboxI am interested in.. how the lightning discharge initiates, the initial point in a cloud where lightning starts its short journey.Quote from: Theboxa cluster of positive charged particles, the cluster particles would want to repel each other The cloud has an electric charge, which repels like charges. It is surrounded by a volume of air which does not have the same charge. So the initial tree-like structure of discharges effectively reaches every part of the surrounding air, equalising the cloud's charge with the charge in the nearby volume of air. This process is most effective where the electric field gradient is strongest, which is near the source of the charge (the cloud, or a lightning rod on the Earth).To initiate a conductive path from cloud to ground, it has been suggested that (at least in some cases), cosmic rays from outer space strike the Earth's atmosphere, shattering the atoms in the atmosphere, and creating a variety of ionised paths through the cloud to ground. The charge in the cloud (and surrounding air) then follows this conductive path, further ionising it, and turning it into the familiar lightning bolt. Quote from: TheboxCentripetalI think that you are using "Centripetal" here quite literally and accurately as a "force towards the center". However, physicists normally use it only in the context of a body rotating around another body, like a stone whirled on a string, or a planet circling a star (at least, English-speaking physicists). We would not use it to describe static charges surrounding a cloud being attracted to a cloud.(Of course, there is probably a way that you could use centripetal in the context of a spinning tornado, but lightning still happens without a tornado..)
Quote from: Thebox on 19/03/2015 08:39:25Quote from: alancalverd on 19/03/2015 06:35:42Why "say the ground is negative" if it's actually positive, as you can see from the streamer charge, and as I said in my explanation? "What goes up" is then positive charge, and "what comes down" is negative charge. The (mostly neutral) air in between just gets cooked because it's in the way.What comes down is the same has what goes up, neither can be negative?NO! I just said that what goes up is the opposite of what comes down!!!QuoteI get the cloud is a negative mass, that extracts a positive from the air , the ground and also the sun.I don't know where you "get" that from. Convection within the cloud separates charges (like a VandeGraaf generator) so that the bottom of the cloud acquires a negative charge and the top acquires a positive charge. The positive charge rarely discharges to ground because a good thundercloud can be 30,000 feet high, with the base only 2- 3000 ft above ground. QuoteA firstly unseen action, and when the cloud can not absorb any more energy the cloud surges and sends back through itself of an unseen stream, a backwards surge giving the effect of seen lightning? Intra-cloud discharge can occur but most of what is observed is cloud-to-ground discharge. QuoteI am going fishing soon for 24 hrs so it i will be friday night before I respond. Good luck! I'm off to spend a day in an operating theatre - look forward to catching up with you later.QuoteIf you could have a mass of solely negative charge, and surrounding that mass was a positive charged atmosphere, the positive charge would do its best to centripetal find and attract to the center of mass of the negative object where the object is it's most density? I think you mean that opposite charges attract. I'd agree
Hope you had a relaxing and successful fishing trip. I hope you're not going to bait us too much on your return []With the notable exception of jccc, we are trying to give you explanation appropriate to a forum. That means the answers are short ones rather than textbook size and so make some assumptions about your general knowledge. Physics is a collection of separate but interrelated areas of knowledge and it's not possible to explain every interrelationship in a forum. However, if someone is a genuine seeker of knowledge we will do our best, but as we have said before you need to do more background reading and study.You often say that you understand things, like plasma, charge, discharge, interference, etc but then you ask questions or make statements which indicate you don't.Quote from: Thebox on 19/03/2015 08:39:25A firstly unseen action, and when the cloud can not absorb any more energy the cloud surges and sends back through itself of an unseen stream, a backwards surge giving the effect of seen lightning?The cloud does not surge or send anything through itself. It is the charged particles and electrons that do the moving. Quote from: Thebox on 19/03/2015 08:39:25If you could have a mass of solely negative charge, and surrounding that mass was a positive charged atmosphere, the positive charge would do its best to centripetal find and attract to the center of mass of the negative object where the object is it's most density?Why do you use the word centripetal again? What curved path are you thinking about?Ignoring centripetal. Both the +ve and -ve charged areas (avoid using mass in this context - see PS at end) would attract each other. Where they meet equalisation of charge (which is discharge) will occur. Which one does the moving depends on how fixed the objects or zones of charge are and which are free to move. Where both are fixed, charge can move through intermediaries such as ions or charged particles - dust, water droplets, etc.It is not correct to talk about the centre of mass of a charged object as electrostatic charges do not work like gravity. Similarly charge density does not work like the density of mass. It is much better to think of charge on the surface of an object.I suggest you study how charge accumulates through transfer of electrons. Then look at ions. Then think through how charge transfers from one area to another either through direct transfer of electrons or via intermediate ions and charged particles.Any specific questions we'll try to answer.Edit:PS added - although we speak of a mass of things, meaning a large collection, it is easy to become confused between the mass of an object, it's density, and the effect of gravity, compared to electrostatic attraction and charge density - they are not directly comparable.
Quote from: Thebox on 18/03/2015 23:26:04What goes up and what comes down is the same stuff right?Yes, electron flow through ionized air and water vapor. When there's a surplus in the clouds, the flow goes to the ground. When there's a surplus in the ground, the flow goes to the clouds.