studiot

Thank you, Larry, for picking that up. Unfortunately I can't now correct post142. The energy equation should, of course contain velocity squared terms. [math]\frac{{V_1^2}}{2} + {P_1}{v_1} + g{z_1} + {U_1} + Q - W = \frac{{V_2^2}}{2} + {P_2}{v_2} + g{z_2} + {U_2}[/math]...........3 I started by using all capitals for quantities, then realised I had two Vs, one for velocity and one for volume and things wnet awry when I sorted that. The work equation does not apply to distributed mass such as fluids, it applies to identifable bodies such as airfoils. Edit I see the error carried right through so the proper Bernoulli equations are without losses/inputs [math]\frac{{V_1^2}}{{2g}} + \frac{{{P_1}}}{{\rho g}} + {z_1} = \frac{{V_2^2}}{{2g}} + \frac{{{P_2}}}{{\rho g}} + {z_2}[/math].............1 and with losses/inputs [math]\frac{{V_1^2}}{{2g}} + \frac{{{P_1}}}{{\rho g}} + {z_1} \pm h = \frac{{V_2^2}}{{2g}} + \frac{{{P_2}}}{{\rho g}} + {z_2}[/math]...............2 I have also now numbered the equations for future reference.

One of the most annoying traits of the input editor is that , depending upon the position of my mouse, the editor also starts off whatever icon my mouse pointer is headed, be it underline, strikeout, lists, links overlays Wouldn't it be just fantastic if it was fixed so this did not happen.

Of course depending upon the nature of your subject, here is the classic mathematical study poster http://prefrontal.org/files/posters/Bennett-Salmon-2009.pdf

Larry, I didn't notice the density appearing in my equation, so how could it affect it? Please bear with me I haven't labelled my variables etc, as I hope that all will become clear in the next post(s). But your post has encouraged me that the interest is still there to complete this discussion.

I did say I would post more detail. This will take several posts and I have been trying to get some stuff together for this. This post will be an introductory post to collect together some preliminaries, for ease of referral. First dimensional analysis is important in Physics, but particularly important in fluids. Some useful dimensions are Now it can clearly be seen that neither pressure nor velocity is energy. So in order to write an equation we need to bring all our terms to a common denominator, preferably a simple one. Engineers have traditionally used 'head' as this common denominator, which has the dimensions of length. Energy is just too complicated. Here are some quantities that have the dimensions of length or head. [math]{\rm{Head}} = \frac{{{\rm{Energy}}}}{{{\rm{Force}}}}{\rm{ = }}\frac{{{\rm{Energy}}}}{{{\rm{Weight}}}}{\rm{ = }}\frac{{{\rm{Pressure x Volume}}}}{{{\rm{Force}}}} = \frac{{{{\left( {{\rm{Velocity}}} \right)}^{\rm{2}}}}}{{{\rm{Acceleration}}}}{\rm{ = }}\frac{{{\rm{Pressure x Volume}}}}{{{\rm{Mass x Acceleration}}}}{\rm{ = }}\left\{ {\frac{{{\rm{Pressure}}}}{{{\rm{Acceleration}}}}{\rm{x}}\frac{{\rm{1}}}{{{\rm{Density}}}}} \right\} = {\rm{Length}}[/math] Now we need some equations of motion to employ these quantities. The simplest form of Bernoulli's equation (in terms of head) as applied to a pipe or duct as in post 83 is [math]\frac{{V_1^1}}{{2g}} + \frac{{{P_1}}}{{\rho g}} + {z_1} = \frac{{V_2^1}}{{2g}} + \frac{{{P_2}}}{{\rho g}} + {z_2} = H = {\rm{A constant}}[/math] Note that all these terms have the dimensions of length. This equation is applied to a pipe running full, it does not apply to a pipe only partly full. Further the fluid must act in an incompressible way. However it can be used (with modifications) for a pipe with or without friction, The fluid can have viscoscity or be inviscid And we can introduce machines such as Zet's airfoil in the stream as some sections of the pipe. Each of these adds a term to the equation, increasing or reducing the head at any point. So friction and fluid driven machinery (eg airfoils) introduce a negative head, whilst pumps introduce a positive head, section 1 (subscripts) is taken before the extra and section 2 after it. [math]\frac{{V_1^1}}{{2g}} + \frac{{{P_1}}}{{\rho g}} + {z_1} \pm h = \frac{{V_2^1}}{{2g}} + \frac{{{P_2}}}{{\rho g}} + {z_2}[/math] Where +h is the work added by a pump or -h taken out by a turbine. Compressible fluids, principly gases, have several more terms and are best dealt with by what is known as the enrgy equation. [math]\frac{{V_1^1}}{2} + {P_1}{v_1} + g{z_1} + {U_1} + Q - W = \frac{{V_2^1}}{2} + {P_2}{v_2} + g{z_2} + {U_2}[/math] Finally we will need an estimate of the work done by the airfoil machine against gravity. The work equation for any object lefted in a gravitational field is [math]W = \left( {\frac{1}{2}mV_2^2 - \frac{1}{2}mV_1^2} \right) + \left( {mg{z_2} - mg{z_1}} \right)[/math] We can convert this to a head loss by dividing W by the airfoil weight, which will produce some interesting results when applied to the post83 setup.

Thank you again, imatfaal, but I'm not sure of your point(s) here. I am just testing a few things out using MathType, which I seem to have working for me for once. Eventually I want use these items in a particular thread.

Thank's imatfaal, that's now created a bookmark trail for some useful other threads. Others may also find these useful. However I didn't see anything about the subject of this thread, posting a table. test [math]{\rm{Head}} = \frac{{{\rm{Energy}}}}{{{\rm{Force}}}}{\rm{ = }}\frac{{{\rm{Energy}}}}{{{\rm{Weight}}}}{\rm{ = }}\frac{{{\rm{Pressure x Volume}}}}{{{\rm{Force}}}} = \frac{{{{\left( {{\rm{Velocity}}} \right)}^{\rm{2}}}}}{{{\rm{Acceleration}}}}{\rm{ = }}\frac{{{\rm{PressurexVolume}}}}{{{\rm{MassxAcceleration}}}}{\rm{ = }}\left\{ {\frac{{{\rm{Pressure}}}}{{{\rm{acceleration}}}}{\rm{x}}\frac{{\rm{1}}}{{{\rm{density}}}}} \right\} = {\rm{Length}}[/math]

Maths and English education is allegedly plummeting in the US and the UK Does Donald Clark's wry comment have any bearing? http://donaldclarkplanb.blogspot.co.uk/2015/02/the-problem-with-maths-is-english-20.html

As a matter of interest, conventional geologists are not insensitive to other mechanical ideas. Indeed these days they like to try them out practically in models. Here are a couple of extracts from Twiss and Moores. The first shows mountain building as a result of tension. The second shows mountain building as a result of upwelling. I think the experimenter's ingenuity is to be commended. While you are a way the final chapters of Twiss and Moores Structural Geology and Ramberg's Gravity, deformation and the earth's crust would be worth a punt.

I can think of another tech forum that has lost many long standing members because it wasted a lot of money trading 'up' and moving from Vbulletin to XenForo. [math]\begin{array}{*{20}{c}}{{\bf{Acceleration}}} \hfill & {{\bf{L}}{{\bf{T}}^{{\bf{ - 2}}}}} \hfill \\{{\bf{Force}}} \hfill & {{\bf{ML}}{{\bf{T}}^{{\bf{ - 2}}}}} \hfill \\ {{\bf{Energy }}} \hfill & {{\bf{M}}{{\bf{L}}^{\bf{2}}}{{\bf{T}}^{{\bf{ - 2}}}}} \hfill \\ {{\bf{Pressure}}} \hfill & {{\bf{ M}}{{\bf{L}}^{{\bf{ - 1}}}}{{\bf{T}}^{{\bf{ - 2}}}}} \hfill \\{{\bf{Velocity}}} \hfill & {{\bf{L}}{{\bf{T}}^{{\bf{ - 1}}}}} \hfill \\ {{{\left( {{\bf{Velocity}}} \right)}^{\bf{2}}}} \hfill & {{{\bf{L}}^{\bf{2}}}{{\bf{T}}^{{\bf{ - 2}}}}} \hfill \\ {{\bf{Head}}} \hfill & {\bf{L}} \hfill \\\end{array}{\rm{ }}[/math] Yippee, I'm getting there. Now all I need is a way to see the code in a few weeks time, ie the next time I want to do a table. Edit I just discovered that if you click on the above table the image overlay opens and includes the code. Someone really ought to write a help section for the forum, explaining the functions, 'cause some are really cool.

b has the units of volume so the formula per mole is [math]P = \frac{{RT}}{{\left( {V - b} \right)}}[/math] It is a cut down Van der Waal's equation.

Thank you Sensei for providing that background +1 It is no reflection on you personally, but a sad statement of 'progress' that I would expect an 8 year old with a paper and pencil to be able to draw a better table than that. I certainly could at that age. In Word or Frontpage I can make a simple table that where I can make the rows and columns of sensible size for the job, with or without separating lines, and then type the data into the spaces. I particularly wanted to use this site's excellent superscript facility to display a table of quantities and their dimensions for a dimensional analysis in another thread so I might try your suggestions. That was one drawback to endy's link (and also Word/Frontpage) - the table generator doe not allow this.

Not exactly my point. 2 millionyears v 200 million years is a big difference. If you look closely at my four maps you can see that two hotspots, roughly the presentday Azores and Tristan-Walvis hotspots , (Nos 1 and 42 here) http://en.wikipedia.org/wiki/File:Hotspots.jpg Doming up under the landmass of the 200MY BP starting the North Atlantic and South Atlantic oceans respectively. At this time there was no oceanic basin , ridge or floor. The spreading of the ocean floor, the building of the ridge and the eventual joining of the two oceans can be followed over the first three maps for 150 MY. Note that the northen end to this ridge between Greenland and Canada becomes a side spur and the ridge branches and extends further north in th last (50MY) map with the upwelling of the modern Icelandic hotspot. You have not fully appreciated the implications of the regular increase in age of the ocean floor rocks from as distance increases both east and west of the ridgeline. If, as you contend, the ridge is the result of pre-existing being thrust up under pressure from both sides (you cannot have compression from one side only) then, by definition of pre-existing, the ridge would be older rock. However some of the ridge rock is so young as to be dated 0 Y. If, you prefer to contend that compression led to the original upwellings then that upwelling cannot have been the present day ridge material because even the space it now occupies did not exist 200 MY BP, let alone the material to occupy it. Let me take this opportunity to wish you wwell in your break and to thank you for focusing attention on an interesting subject. I do not endorse this site, but have you come across the continually expanding theory? (Not expansion/contraction cycles like yours) http://www.expansiontectonics.com/page3.html Edit today was pancake day (Shrove Tuesday). I don't know if you have ever cooked pancakes, but you can see the doming produced by hot upwelling beautifully illustrated in the pancake pan as the hot air bubbles up from underneath.

Greenwood & Earnshaw refer to "poorly formed graphite" for the structure of coke. Wells gives more detail It should be noted that there are two full forms of the graphitic structure, with slightly different interplanar separations. So the structure would appear to consist of crystallites, being small pieces of containing the regular hexagonal graphitic planes, but not fully aligned and linked in the third dimension; the crystallites being randomly oriented with respect to each other, like the grains in a metal.

Good morning, Billy and welcome to ScienceForums. So just how long is a piece of string? The card you link to looks good and solid in itself, but needs additional circuitry to make it do anything. I particularly like the high current connection provision. But no one can really make any more detailed comments without some idea of your application and source of power.

Thank you endy for being the only one interested to help, +1, but I have no idea what you are talking about. I can certainly see why no one bothers to post tables, it is far to difficult. It is just sad that I am not the real sufferer, because I can see what I want in my mind's eye. I just cannot communicate it to those who would like to know.

[table] 0neTwoThree abc def [/table] 0neTwoThree abc def [ta] 0neTwoThree abc def [/ta] Wow this is fun, it wipes out each attempt [ta] 0ne Two Three [/tr] abc def [/table] [/ta] I give up

Still can't get tables to work Can anyone help please? I need a simple 1,2,3, of what to do create a table. Thanks Acceleration LT-2 Force MLT-2 Energy ML2T-2 Pressure ML-1T-2 Velocity LT-1 (Velocity)2 L2T-2

Thank you for the nice pictures, but again a digression. Do you really think 200 million years is simultaneous? This short line requires full and detailed consideration as it is the basis of the conventional history of ocean floor spreading. Please note there is almost overwhelming support evidence behind this part of the story. So much so that this now forms part of the high school curriculum. http://www.earthlearningidea.com/PDF/198_Atlantic_opening.pdf Here is the conventional history made from substantial bottom sampling. I don't think it can be fairly called anything approaching simultaneous, even on a geological timescale. My pic is only greyscale and not up to your standards, but it shows the essential information clearly.

Crustal material falls into two distinct and different material types that are easily recognisable. Oceanic crust and Continental crust. Orogeny can be the result of single or episodic magmatic upwelling It can also be the result of penetrant impact. This refers to the shear generated by pressure from a sharp object such as the Indian plate, which is small compared to the Eurasian plate it is pushing into. Think about pushing into your carpet with your finger. You will generate ruggles, but not by compression. Occam also needs to consider the age sequence and composition of the rocks on the bed of the Atlantic which definitely suggest and fit with epidsodic upwelling of mantle material as opposed to compression of continental crust.

Hello unconstrained and welcome. I hope your recovery is going well. Since I am not a member of the New Jersey Institute of Technology I cannot use the link, but I assume the attached images are the same. We do not complete homework for you but here is a start. Since you have missed some lectures please ask if there is anything you need explaining in more detail. Your rate equation is [math]Rate = k{\left[ {NO} \right]^x}{\left[ {{O_3}} \right]^y}[/math] Do you understand this? Take logs (base 10 or natural) [math]\log (rate) = x\log \left[ {NO} \right] + C[/math] Where we are told that the concentration of Ozone is constant so the only variable is the concentration of Nitric Oxide. Can you see this? Log(k) is also a constant so I have incorporated both these into the constant C [math]C = cons\tan t = \log (k) + y\log \left[ {{O_3}} \right][/math]

A recent discovery down under has bearing on this. https://twitter.com/eurogeosciences/status/563786008823472128

Well I've never seen a fluid than can support a vertical free surface like that.

This is exactly where using the apparatus as a control volume comes in handy. Zet specified (I asked him) that there was a vacuum above the top surface of the fluid in the column. So whether the fluid would move at all depends upon the height of the column and gravity. Using a control volume would specify a sensible pressure upon the top surface, opposed by a side pressure from atmosphere when the door was opened.

Larry, how would you start the motion?