studiot

Agreed the 't' test would be appropriate. Unity, since you are doing so well, perhaps you would like to explain about samples and populations since the object of the exercise is to compare populations by comparing samples from different clam populations. A question for bluebird Do you think this should be a one tailed test or a two tailed test?

You need to distinguish carefully between the wave and the vibrating particles or elements carrying that wave. The motion of any wave is not the same as the motion of the particles. The speed of any wave is independent of the speed of the source. This includes the speed of light waves however light wave are unique in that the their speed is also independent of the speed of the observer. A medium is an array of linked vibrating particles. Once a wave has left the source and is being transmitted by the medium its speed is normally a constant determined by the physical properties of the medium.

This is a very long term discussion, with one post per week or so. Do you only have limited internet access? Or do you have to translate replies? I don't fully understand what course you are studying. The folk classification is for a particular groups of sedimentary rocks, not sediments themselves. What you have posted is more like a soil classification. Are you studying the rocks or the sediments? For what purpose? Here is a good resource, it includes answers to your question about measurement. Post again if you want more. http://environment.uwe.ac.uk/geocal/SoilMech/classification/default.htm

I was looking for a sketch.

Sure, but it makes a good movie eh?

Earthquake effects do not work like this. The Quake is a travelling wave. This means that is has a wavefront. This is a sharply defined section. One side of the wave is doing one thing (perhaps going up) The other side is doing something else (perhaps going down) This is called differential movement. So as the wavefront passes through the building, different parts of the structure can be moving in opposite directions. This snaps floor slabs, pushes up sidewalls and detaches them and much more. Unless the building is very tiny ( and therefore probably safe) the quake wave does not affect the whole building at once. That is the point.

Not really. soil mechanics is quite a specialist (and technical) subject. I can do the fancy maths if you prefer.

I'm trying to be as explicit as I can. If the P wave 'shakes up' the soil then it may loose it's strength, like the ketchup. This was only condition 1 on my list. Condition 2 is different again. The weight of soil (as with anything ) is w =mg. That is the mass times the acceleration due to gravity. Usually this is the only force acting on the soil. But if there is an acceleration due to the P wave then a second force is applied. This may be sufficient to make a previously stable bank of soil unstable.

Sorry but I didn't say that either. What happens when you shake a bottle of tomato ketchup?

So am I What does all this stuff have to do with the original post?

Sure thing, I am happy to discuss further if you wish.

I didn't say any of that, read it again. The P wave affect the foundation earth material. rather than the building. PS do you understand that 'foundation' refers to the earth or ground supporting the structure, not the structure itself?

S waves cause actual differential movement of parts of a structure. If this cannot be accomodated by the structure, it will fail. P waves alter the characteristics of the foundation earth material, due to the accelerations involved in the wave. This has two effects. Firstly it can cause the foundation material to loose some bearing capacity, and therefore the ability to support all or part of a structure. Secondly all loaded foundations have failure planes and other surfaces (eg the slip circle) which are loaded by the earth above and any structure on that superficial earth. The acceleration of this material increases the force on it, because force = mass x acceleration. This can take it outside the support range of the plane or circle (in shear), causing failure of the earth. This applies in particular to cutting sides and embankments.

Fred Champion The point was (is) that the state of an object provides no link to any sort of deduction about time. The formal statement of Pauli that I have seen does not include "at the same time", or any other reference to time, because a reference to time is neither necessary nor proper. In order for the state of an object to link to time it would have to include the recognition of some sort of change (velocity, momentum,etc) and change is recognized only over two or more states. A correct description of state will include only one state (the one described) and not others. The state of an object is much like the photo of a clock. While a series of such photos may imply an intelligence (with the necessary memory) capable of recognizing change, it does not imply any phenomenon beyond that, and a single photo of a clock provides no indication of change at all. You have not addressed my question, which was quite specific. The complete wavefunction describing a many particle state is antisymmetric under the exchange of any pair of identical fermions and symmetric under the exchange of any pair of identical bosons. So first of all only fermions follow the Pauli exclusion principle, which follows directly from the above statement. Secondly, the Exclusion Principle that no two identical fermions (from the same system) can have the same set of quantum numbers, applies throughout time. That is why time is not mentioned. Because it can never happen. None of the foregoing prevents interpenetration, which is another name for quantum tunnelling, upon which the computer I am writing this depends for its action.

This is like saying, "If I had a pocket cold fusion device I could make a lot of cheap electricity" and concentrating on the easy bit - the design of the electricity generator part. Try this estimate. Take a simple harmonic oscillator and calculate the maximum particle velocity at a range of frequencies, perhaps on a spreadsheet. Since the vibrating molecule is an object with mass, relativity provides an upper limite of this vibrational speed and therefore velocity. I think, however, that for all known materials, the vibrational energy would exceed the bond energy long before this limit was reached, so you would also have to postulate a super material where this was not so.

I don't know. To have a capability to excite a wave of a given frequency you have to have a viable (in theory) mechanism for excitation. I can't think of one can you?

The velocity of sound in a given material is largely independent of frequency. Further, whilst the frequencies attainable in ultrasonics have some overlap with the lower end of EM radiation frequencies, they do not reach that of gamma radiation.

This is the first time I have ever seen a formula that includes a registered trade mark! But I agree that is way too complicated to start off with. But I was not asking for this, I was asking about the mechanics of your diagram. Your diagram should be a free body diagram or rather set of diagrams since it is a 3 dimensional situation. You are asking about forces and moments on the tyres so I would suggest the free body should be the wheel/tyre assembly. Given this, the answer to my question where does Fsr act is "Fsr acts on the hub" assuming it the the froce applied by the forks to the wheel. From what I can see (if you are saying Fc is the frictional force) Fc acts perpendicular to the plane of your diagram not in it. Also as you have drawn it the velocity is perpendicular to the plane of your diagram. If you have been taught Newton you need to introduce the centripetal acceleration, which is in the plane of your diagram. You did not answer my first question about equilibrium analyses. Incidentally I cannot see whatever you have linked to in the first post. Please post the necessary information in the thread, this is also forum policy.

Fair, if very brief, comment.

Did Pauli claim this? It is not part of quantum theory, in fact it is contrary to quantum theory, which permits interpenetration of 'object', subject to Pauli's rules.

You have some good ideas and keen perceptions. Unfortunately you have jumbled some of these up where they do not run together. I am trying to help you separate them, as it will help see things more clearly. Alven's work has nothing to do with terrestrial conductivity. Terrestrial conductivity is not a simple subject, because of the size of earth relative to any electrical connection. Strangely Coulomb was the first to investigate the mathematics of this, although he did not do so in relation to electricity. The shape of the conductivity isobars is the same as Coulombs solution to the bulb of pressure (ie the pressure distribution) under foundations, which he did study. The conductivity plots are 3 dimensional, by the way. It is just plain wrong to think that any significant current flows through insulating rocks such as granite. The resistance of such rocks is enormous in any direction. I did not say that anything attached to the Earth is the same as the Earth I said it has the same motion. So any phenomenon due to that motion will be common to both. Both are affected by the magnetic field of the Sun (which is much weaker than the Earth's at the Earth's orbit) as both are in motion through it. It was this effect Alven was describing.

Congratulations on realising that aspect of an electrical grounding system. Most people misunderstand the action of grounding. No the Earth is not a very good conductor in that it has medium to high resistivity, and with some rocks eg granite very high resistivity. But it also has a very large cross sectional area so when we divide one large number (the resistivity) by another (the cross section) the apparent resistance is much smaller. But the real reason that the earth works as a ground is its abilty to maintain its potential, regardless of the charge flow into or out of it (for any practical charge flow we can create). I do not know if core spins at a sufficiently different rate to have a significant effect. But the strength of the field is sensibly constant over short times, at any point on the surface. It is the rate change of the field which induces the current, either by relative motion between the conductor and the magnet or by rapid change of the field. I am not sure if you quite picked up on my point about conductors attached to the Earth. Anything attached to or part of the Earth is not moving relative to the Earth's field, so no current is induced as a result. In the Early to middle part of the last century a physicist called Alven won a Nobel prize for his work on electric effects in gas plasmas. He also developed an electromagnetic theory about the electric effects in clusters of stars (which contain a lot of plasma) and the induced currents caused by spinning galaxies. The aspect of this theory is it uses simple conventional theory to explain many astonomical phenomena without a 'big bang' but it did not catch on, although it has not been disproved. https://www.google.co.uk/search?q=hannes+alven&hl=en-GB&gbv=2&oq=hannes+alven&gs_l=heirloom-serp.3..0i10l6j0i5i10i30.9047.10109.0.10812.7.7.0.0.0.1.110.734.2j5.7.0....0...1ac.1.34.heirloom-serp..1.6.609.PBpWrwbmRCQ

You need to work on your diagram before doing any calculations. Do you understand that the bike is not in equilibrium so you cannot use an equilibrium analysis directly? How is Fsr applied to the wheel? What is Fc ? Friction or circular motion forces? On the subject of the curvilinear motion, are you considering accelerations (Newton's solution) or Quasi Equilibrium (D'Alembert's solution) ?

No problem whatsoever, airing legitimate scientific thoughs and questions like yours is the purpose of this forum. Yes indeed the Earth carries its magnetic field through space around the Sun with it as it goes. It also rotates that field as it spins on its axis. In order for this moving field to create a current it must interact with a conductor, that is not moving with the Earth. In other words any conductor mounted on the Earth has the same motion as the Earth and so experiences no change in the terrestrial field due to the Earth's motion. So your pickup conductor would have to hang in space above the Earth. How would you get it up there? How would you keep it up there? How would you connect to it? Bear in mind that it could not 'hover' over one spot. Charged particles in space around the Earth are not mounted on the Earth and do not posses its motion. These are affected by the motion of the Earth's magnetic field as I indicated earlier. These are the 'winds' . Google has some very pretty pictures of the Van Allen Belts. https://www.google.co.uk/search?hl=en-GB&source=hp&q=van+allen+radiation+zones&gbv=2&oq=Van+Allen&gs_l=heirloom-hp.1.6.0l5j0i10j0l2j0i10j0.1406.6125.0.10859.10.10.0.0.0.0.125.1016.6j4.10.0....0...1ac.1.34.heirloom-hp..0.10.1016.iVBfU6UEgzo