studiot

There is some truth in that (using your definition of a battleship, although this was actually set by the US - UK limitation following the naval arms race of earlier times) , anyone remember the Belgrano ? Even back to ancient Mediterranean (and I believe ancient China) sea battles, there was a major difference between massive fleet engagements and those involving a single or handful of ships.

Thank you for the reply MigL. I don't find your statement convincing, however. Surely the instant that a particle crosses a dashed line there must be a local entropy change, which must include the whole compartment. I am exploring the compatibility of 'Laws' from different parts of Physics here and in particular testing the boundaries of classical thermodynamics. It will be interesting to here what other members have to say.

Whilst musing on a statistical question I had a thought. Consider an isolated box of gas. The expectation is that the particles will be evenly distributed throughout the box. This is shown in fig 1 where there are 3 particles in each subdivision. Now as the particles move about consider the situation where two particles have temporarily moved from other divisions, B and D into division A. This is shown in fig2 This constitutes a local decrease in entropy in A and an corresponding increase in B and D since the overall or global entropy must remain constant. Now this must be true however small the divisions or however large the box. So the question arises "How fast does the local balancing of total entropy spread throughout the box?" and ""Is this some sort of action at a distance in a big enough box?"

1) A taylor series, like any converging series (do you understand converging) may be used to estimate in numeric calculation or stand in for algebraically in formula an expression that is difficult to handle. If the series convderges quickly enough (it often does) we can ignore all terms after the first n, for some small n. There are criteria for deciding how many terms to use. The process of discarding the rest is called truncation. Wolfram has a good explanation https://mathworld.wolfram.com/TaylorSeries.html 2) An aperture is an opening, which is used to describe the 'size' of something or the size of something being measured or that can pass through. So this term is widely used in geosciences. Polyzoa (Fenestrilina) colonies form a basket like weave with apertures in the basket to filter and trap particles washing through. Acidic groundwater percolating through susceptible rocks (eg limestone) solution weather apertures in the solid rock. In photogeology the aperture is the camera opening that controls the amount of light entering. Similary magnetic sensor arrays and seismic arrays have an aperture sensitivity. These control the amplitude and frequency that can be accepted by the arrays. Other wave phenomena (eg ultrasonic) have similar use of the term. https://en.wikipedia.org/wiki/Seismic_array

Thanks +1

Hidden beneath all those big words and phrases is the fact that the random walks described are more like drunk wandering the grid pattern of streets at night. He takes a 'random' decision at each intersection but is constrained as to the four directions he can take. Furthermore it does not matter how much time he takes deciding or walking. This is a single discrete random variable. A gaseous particle, on the other hand does not take decisions. Its random walk come from being buffetted by other particles in a random fashion. This random fashion occurs at random instants, imparting random momenta in random directions. All of these three variables are fully continuous independent random variables.

I really don't like the (double) slit experiment as it is so often used to present a slick 'Look how clever and tricky I am' point of view of the combination of waves. (Yes it does also have legitimate significance) Here is a simple sine wave Do you understand 1) What is being measured along both axes 2) The difference between a travelling wave and a standing wave. This is very important when it comes to combining waves.

Nice topic +1 But. Beware of confusing random progression through a mathematical graph with a spatial random walk for say a gaseous molecule.

I might be helpful to know your brief and source material, since this is a writing assignment. Is it a comprehension task, based on a given passage in English, or Is it your own composition ? I ask because it is nearly true but scientifically the word plastic is not the same as you have indicated. Your use is correct from an English point of view as modern usage has mixed up 'plastic' with particular artificial materials. Plastic is an older term relating to certain types of mechanical behaviour of any material whatsoever. Natural or artificial. Basically when plastic material is deformed by some load or force it stays deformed after the load is removed. It does not spring back like elastic materials. The difficulty is that there are some very hard materials included in the plastics category - for example bakelite and some 'hard as metal glues', resin concretes and composites. Usually the word has plastic has the s added (plastics) to create this category. The rest of your description is pretty good. Plastics are energy efficient; the plastic part is formed from synthetic high polymers. Does this help ?

Good for you +1 for encouragement and asking about things. You will find in Physics that you don't meet everything at once, but learn a little about something and then come back again later to learn some more. So I will not tell you all about scalars and vectors, just some stuff to hold onto that may help in diferent situations. Scalars and vectors are part of a heirarchy of types of things (objects) in Physics that are related to coordinate systems. Are you familiar with the idea of coordinates ? As they are objects they have some special properties. At the bottom of the list we find scalars. A scalar has a magnitude or simple numeric value. (Note this could be zero. zero is a perfectly respectable and valid numeric value) This is the same wherever you are, I see swansont has offered mass as an example. So a mass of 1 kilogramme is the same in Timbuctoo as Toronto. Next on the list we have vectors. These not only have a magnitude but they also have a direction. The direction is the link that ties into the coordinate system So we can represent the distance from Toronto to Timbuctoo as a vector. This will tell us not only how far we have to go (magnitude) but also in what direction we need to set off in order to reach the destination. That is enough to be going on with until you confirm about coordinate. I will mention that the next object in the heirarchy is called a Tensor, in case you hear of them. A tensor has magnitude and not one but two directions. But don't worry about them.

My answer to the thread question has to be Before studiot can spell properly.

Sounds interesting, have you got a reference thanks ?

Would that be because it's a hard drive ? That about describes the original T - Model, currently posing as President.

Even a straight line can be twisted about its own axis. That is called torsion.

Are you sure you don't mean hydrophobic?

Yup +1 Used to be one of the standing instructions for wartime foraging (for fuel) - find some cooking oil, preferably clean.

This is a question of Chemistry, not Physics. In order to understand what was going on at that time it is necessary to know that Avogadro was contradicting two Scientists who Wikipedia label as the founders of modern Chemistry, Dalton and Berzelius. They were proponents of Dalton's atomic theory did not acknowledge molecules, but held that in a chemical reaction one atom of A combined with one atom of B to give one atom of C. Dalton and Berzelius made great advances in chemistry but they did not accept molecules so when Avogardro made his hypothesis they fought tooth and nail against and as the great men of their day, this held back progress for nearly half a century. Note Avogadro did not call his hypothesis a Law, but merely stated that if solved the apparent problem of measuring chemical composition by volume. He starts his paper thus (English translation) In turn Gay Lussac had written from experimental evidence Now it was known that I volume of hydrogen + 1 volume of chlorine yields 2 volumes of hydrogen chloride. Dalton proposed that each volume of reactant and product contained the same number of atoms of their respective gases so n atoms of hydrogen + n atoms of chlorine yield 2n particles of hydrogen chloride. 1 atom of hydrogen + 1 atom of chlorine yield 2 particles of hydrogen chloride. But each particle of hydrogen chloride must contain some hydrogen and some chlorine. So the only way this can be true is if the atoms split into parts, which is contrary to Daltons definition of an atom as the smallest indivisible particle. The same difficulty was encountered with other known gaseous reactions such as hydrogen and oxygen, hydrogen and nitrogen, oxygen and nitrogen. Avogadro's paper proposes that if in some gases atoms are joined together into larger particles, containing two or more atoms such that these larger particles, he called molecules, are substituted for atoms in Dalton's proposal Gay-Lussac's Law is automatically satisfied for both reactants and products. He then makes his famous hypothesis He also states that following this hypothesis : the ratio of the weights of equal volumes of two gases A and B must be the same as the ratio of the weight 1 molecule of A to 1 molecules of B. The job was not completed until 1858 by Cannizzaro who extended this to atomic masses. Not sure why so are so deeply interested (but I am pleased someone is). The really important thing Avogadro 'discovered' was the molecule as distinct from the atom and linked this to the connection between weight and volume. There is a really good book about all this by a top notch Chemist called Chasing the Molecule John Buckingham Which is the history (with good scientific explanations) of molecules and chemical formulae in general.

Dessicated air ?

Perhaps it was something I had for dinner. Please explain to me how a wave is possible where this is only one single dimension.

And, of course, if there are real particles to do the absorbing there is not 'nothing', by definition.

Another point to take into consideration is the difference between the virtual particles suggested and real (material) particles is the with virtual particles the end result is always zero ie the always sum to zero, depending upon properties under consideration.

Another complication for the OP to consider is What do you mean by 'is' ? Can something 'exist' whether we have discovered it or not ? It is possible (in fact that is the way we construct them today) to construct the entire number system from nothing. That is repeated copies of the empty or null set.

Interesting question as today we derive Avogadro's Hypothesis (as it was originally called) from the kinetic theory following Maxwell's theoretical derivation. Avogadro himself used a different route. He was concerned with chemical reactions between gasses and explaining the simple relationship between the volumes of gasses entering into chemical combination. Note he said molecules, not atoms. He suggested that the densities of these reacting gasses, under the same conditions of temperature and pressure are in the ratios of their respective masses of their molecules. From this it follows that they are in the same ratios as their molecular masses (then called molecular weights). Since these are all relative to a standard gas (eg taking oxygen as 16) the hypothesis follows for equal volumes.

This is a good explanation of the animation. And also of our universe as we know it. Sure. But not, in my opinion, a good example to quote in relation to a deeper question such as this one that ranges more widely. Energy, for instance, in not a 'thing' at all, but a fictional concept, convenient to our paricular presentation of Physics. Time and its nature is an even more inscrutible concept that has seen many lengthy discussion threads since the inception of SF and way back before. We should examine the questions, In order for something to exist does it need somewhere for it to exist and somewhen for it to exist? Relativity has shown that this condition is not necessary - we have also discussed this at great length here.

One way to approach a difficult problems is to break it down into small steps ie substitute a series of lesser questions in this case. So we have How many ways can something exist ? I suggest a great many. How many ways can nothing exist ? I suggest at most one. So the substutute question becomes Statistically why are we suprised that something exists ?