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A Massive Lake of Molten Carbon Discovered Under The US!

Discussion in 'Coffee Shack (Daily News/Economy)' started by Goldhedge, Apr 25, 2017.



  1. Goldhedge

    Goldhedge Modal Operator/Moderator Site Mgr Site Supporter

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    A Massive Lake of Molten Carbon The Size of Mexico is Discovered Under The US
    4 climate, earth, Environment, Tectonic, USA 2:28 PM


    [​IMG]

    Scientists uncovered a huge reservoir of molten carbon situated under the Western US, 217 miles (350km) beneath the Earth's surface

    • Situated under western US, 217 miles (350km) beneath the Earth's surface
    • Upper mantle could contain up to 100 trillion metric tonnes of melted carbon
    Scientists have discovered a huge reservoir of molten carbon deep beneath the western U.S.

    A huge well of molten carbon that would spell disaster for the planet if released has been found under the US.

    Scientists using the world's largest array of seismic sensors have mapped a deep-Earth area, covering 700,000 sq miles (1.8 million sq km).

    This is around the size of Mexico, and researchers say it has the potential to cause untold environmental damage. The discovery could change our understanding of how much carbon the Earth contains, suggesting it is much more than we previously believed.

    It would be impossible to drill far enough down to physically 'see' the Earth's mantle, so a team of researchers used a massive group of sensors to paint a picture of it, using mathematical equations to interpret their results.

    The study, conducted by geologists at Royal Holloway University in London, used a huge network of 583 seismic sensors that measure the Earth's vibrations, to create a picture of the area's deep sub surface.

    Known as the upper mantle, this section of the Earth's interior is known for by its high temperatures where solid carbonates melt, creating distinctive seismic patterns.

    What they found was a vast buried deposit of molten carbon, which produces carbon dioxide and other gases, situated under the Western US, 217 miles (350km) beneath the Earth's surface. As a result of this study, published in Earth and Planetary Science Letters, scientists now believe the amount of CO2 in the Earth's upper mantle may be up to 100 trillion metric tons.

    In comparison, the US Environmental Protection Agency estimates the global carbon emission in 2011 was nearly 10 billion metric tons – a tiny amount in comparison.

    The deep carbon reservoir discovered will eventually make its way to the surface through volcanic eruptions and contribute to climate change albeit very slowly, but a sudden release could have dire consequences.

    Dr Sash Hier-Majumder of the University of London's Department of Earth Sciences led the study. He said: 'The residence time of this carbon in the mantle is relatively large (nearly 1 billion years), so this reserve is not an imminent threat.'

    'But one important mechanism by which carbon, sinking into the mantle via a subducting oceanic plate, can make it's way back to the surface is by arc volcanism.'

    'Arc volcanism returns between 30-40% of the total subducted carbon back into the atmosphere. The remaining carbon stays in the mantle for a much longer.'

    He added: 'We might not think of the deep structure of the Earth as linked to climate change above us, but this discovery not only has implications for subterranean mapping but also for our future atmosphere,'

    'For example, releasing only one per cent of this CO2 into the atmosphere will be the equivalent of burning 2.3 trillion barrels of oil.'

    'The existence of such deep reservoirs show how important is the role of deep Earth in the global carbon cycle.' As a result of this study, scientists now believe the amount of CO2 in the Earth's upper mantle may be up to 100 trillion metric tons.

    In comparison, the US Environmental Protection Agency estimates the global carbon emission in 2011 was nearly 10 billion metric tons – a tiny amount in comparison.
    The area covered by the study includes Yellowstone National Park, where previous research has uncovered evidence of a supervolcano which could also spell danger for the planet.

    The volcano at Yellowstone National Park in Wyoming and Montana sits atop a huge reserve of molten rock and last erupted 640,000 years ago.

    It releases around 45,000 metric tonnes of carbon dioxide each day. If it were to erupt, it would be one thousand times as powerful as the 1980 Mount St Helens eruption and have the potential to blanket the US in a 'nuclear winter'.

    While it has lain dormant for more than 70,000 years, scientists say that we can't rule out the possibility eruption this may some day take place - although they say the chances are extremely slim.

    The Grand Prismatic hot spring in Yellowstone National Park is among the park's many hydrothermal features created by the Yellowstone supervolcano.

    Experts say there is a one in 700,000 annual chance of a volcanic eruption at the site.


    The study was published Earth and Planetary Science Letters
    Read more at http://www.geologyin.com/2017/04/a-massive-lake-of-molten-carbon-size-of.html#qWHTtUQz1AewHtoE.99
     
  2. Irons

    Irons Deep Sixed Site Supporter Mother Lode

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    We all gonna diah!! Be afraid, be very very afraid!
     
  3. gringott

    gringott Killed then Resurrected Midas Member Site Supporter

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    Nobody ever got out of here alive.
     
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  4. glockngold

    glockngold Gold Member Gold Chaser

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    Fucking scientists!
    They better cut this shit out & get back to work on my sex robot.
     
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  5. Irons

    Irons Deep Sixed Site Supporter Mother Lode

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    Too bad I never figured out how to profit off the fear industry. Lots of people getting rich off that shit.

    .
     
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  6. GOLDBRIX

    GOLDBRIX God,Donald Trump,most in GIM2 I Trust. OTHERS-meh Site Supporter Platinum Bling

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    If it cools just right It's the Solar systems largest diamond. :mining:

    Notice " Experts" always find away to attach "dioxide" to the word "carbon" ? :drive by:
    I never heard of Carbon Paper producing carbon dioxide when I was growing up. So why would a pool of liquid carbon produce carbon dioxide ?

    As it cools it becomes a Rock of Carbon or Diamond.
     
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  7. Professur

    Professur Midas Member Midas Member Site Supporter ++

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    Well there you go. No point is trying to stop generating CO2 anymore. Yellerstone is overdue, and it's gonna dump all this into the air and smother us all. Funny how those scientist missed that point.
     
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  8. Irons

    Irons Deep Sixed Site Supporter Mother Lode

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    The map outline of this pool of grave danger reminds me of Kokopelli. I need more peyote.

    .
     
  9. Irons

    Irons Deep Sixed Site Supporter Mother Lode

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    I just found out the guy who changes my oil is a fierce global warmer. I told him that I don't criticize peaceful religions.
    He flipped out and said it isn't religion it is facts. I replied his high priests not only do not follow his religion they are getting filthy rich off of it. Kinda just like many Christians.

    Then he said it's too late for us to change it now anyway, the damage is done. I laughed a good one and said if the earth is warming we had nothing to do with it and we sure as hell can't stop it. Get over yourself, puny human!

    Now I have to go somewhere else to get my oil changed. . . :(

    .
     
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  10. gringott

    gringott Killed then Resurrected Midas Member Site Supporter

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    I have found that people who have a religious belief cannot be swayed by logic or facts.
     
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  11. Irons

    Irons Deep Sixed Site Supporter Mother Lode

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    Yep. I find fossilized coral all over Michigan, we call 'em Petoskey stones. Coral means this was an ocean at one time, and the Great Lakes were carved out by glaciers. Glaciers are ice. Hmmm.
    So it was a warm ocean, then it froze, then the ice melted and filled all the glacier holes with fresh water.

    I think the real question here is who melted the goddamn glaciers.

    .
     
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  12. FoundingFathers

    FoundingFathers Founder Founding Member Site Mgr Site Supporter

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    Anyway we can tap into that as a source of energy?
     
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  13. Bottom Feeder

    Bottom Feeder Hypophthalmichthys molitrix Gold Chaser Site Supporter

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    and
    Like GOLDBRIX says "So why would a pool of liquid carbon produce carbon dioxide ?"

    For your entertainment:

    Carbon: thermodynamics
    Temperatures:
    Melting point: 3800 [3500 °C (6400 °F)] K
    Boiling point: 4300 [4027 °C (7281 °F)] K

    Carbon Dioxide
    Decomposition
    The substance decomposes on heating above 2000 deg C producing toxic carbon monoxide.
    International Program on Chemical Safety/Commission of the European Communities; International Chemical Safety Card on Carbon dioxide (October 2006).

    https://www.webelements.com/carbon/thermochemistry.html
    https://pubchem.ncbi.nlm.nih.gov/compound/carbon_dioxide#section=Stability
    Climate change - ooooooo carbon dioxide :troll: I so scared.
    Would be more concerned about the one in 700,000 chance of Yellowstone going off.

    looks like idiot science to me.

    BF
     
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  14. ErrosionOfAccord

    ErrosionOfAccord #1 Global Warmer Gold Chaser Site Supporter ++

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  15. Irons

    Irons Deep Sixed Site Supporter Mother Lode

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    They are really cool. I scoop up a lot of them when I'm treasure hunting Lake Michigan and several of the big inland lakes.
    Really nice even proportioned ones I have been keeping to polish later. It takes a couple weeks in the tumbler.

    [​IMG]
     
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  16. Bottom Feeder

    Bottom Feeder Hypophthalmichthys molitrix Gold Chaser Site Supporter

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    Oooooo, pretty rocks, Irons, me want one.

    BF
     
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  17. Scorpio

    Scorpio Скорпион Founding Member Board Elder Site Mgr Site Supporter ++

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    that is the right question,

    instead of lecturing us with the fear mongering and phony science,

    been reading some on the core and mantle lately,

    they state the core is hot, super hot, like surface of sun hot,
    and yet, claim it is a iron core.

    iron that we melt and stuff to make steel out of, ala twin towers come crumbling down due to heat.....but I digress

    supposedly, this iron, is really special iron, having a certain crystalline structure that allows heat to make it stronger, rather than melting it. etc, etc.

    maybe our twin towers + 1 should have had some of this special 'iron'.

    too funny how they just make shit up and repeat it enough for all the slaves to accept it,
     
  18. the_shootist

    the_shootist The war is here on our doorstep! Midas Member Site Supporter ++

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    Seriously, what's next? These people have gone way beyond stupid with all these 'scary' articles of useless bull excrement!
     
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  19. the_shootist

    the_shootist The war is here on our doorstep! Midas Member Site Supporter ++

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    Those are really cool Irons. I'd pay good old Yankee greenbacks for a couple of them to give to the grandkids :)
     
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  20. Irons

    Irons Deep Sixed Site Supporter Mother Lode

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    http://www.ebay.com/sch/i.html?_fro... petoskey stones&rt=nc&_trksid=p2045573.m1684

    HOLY CRAP! I have got to start polishing these things and put them on ebay I had no idea they go for so much money!
    I wonder if I can polish these feckers on a flappy grinding wheel like thing? It takes weeks to tumble polish them.

    When I scoop them out of the lake you can tell they are Petoskey stones but they are really dull. Once they dry out they just look like a gray stone.
    The ones I have are all unpolished. I scooped a big pretty round one out of Lake Michigan @ Frankfort last Friday.
    They are treasure hunting bycatch but I always keep them anyway.

    I will have to get back to you Mr Shootist. I have to see what I can do about getting these things polished.

    .
     
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  21. Scorpio

    Scorpio Скорпион Founding Member Board Elder Site Mgr Site Supporter ++

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  22. Irons

    Irons Deep Sixed Site Supporter Mother Lode

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  23. Eyebone

    Eyebone Midas Member Midas Member

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    So pomp ass of you.

    What happens when we die Mr Know It All?
     
  24. Mujahideen

    Mujahideen Black Member Midas Member

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    Jesus takes you before buddah and says allah Akbar.
     
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  25. Bottom Feeder

    Bottom Feeder Hypophthalmichthys molitrix Gold Chaser Site Supporter

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    That depends on what you believe - your choice

    Sorry

    BF
     
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  26. Bottom Feeder

    Bottom Feeder Hypophthalmichthys molitrix Gold Chaser Site Supporter

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    Don't leave pressure out of the equation, Scorpio. If I remember right Iron is the final result of main sequence suns on their entropy journey. To get elements denser than iron needs cataclysmic action (star collision, super nova or something).

    Not a physicist nor do I play one on TV

    BF
     
  27. the_shootist

    the_shootist The war is here on our doorstep! Midas Member Site Supporter ++

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    Oh hell, I can polish them by just throwing them into my brass tumbler for a day or so.
     
  28. Zed

    Zed Size doesn't count! Midas Member

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    Put out a coin can and tell them you are clearing the beach of unexploded ordinance that .gov is ignoring. You need funds for a better detector... I bet it works.
     
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  29. Scorpio

    Scorpio Скорпион Founding Member Board Elder Site Mgr Site Supporter ++

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    I hear ya, but that takes you back to the big bang theory of which I have zero faith in,

    That would be using the same laws that they hang their hats on,
     
  30. GOLDBRIX

    GOLDBRIX God,Donald Trump,most in GIM2 I Trust. OTHERS-meh Site Supporter Platinum Bling

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    YEP. Geo-Thermal Iceland uses it the most on a per capita basis.
     
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  31. Mujahideen

    Mujahideen Black Member Midas Member

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    Don't quote me here but I think scientists believe iron is at the core because of the magnetic field that earth has. The flow of liquid iron apparently creates a magnetic field.

    I'm interested in knowing what nuclear reaction is going on down there that keeps the magma from cooling after billions (or 6k) of years.
     
    Last edited: Apr 26, 2017
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  32. Irons

    Irons Deep Sixed Site Supporter Mother Lode

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    That is a really good idea but I don't even have to make up a hazard like explosives. If people saw the pounds of rusted jagged metal, broken glass, needle thin rusty nails, rusted jagged bottle caps and fish hooks I scoop out of popular beaches every time I go to one they would probably fill my can with 5 dollar bills.

    I have scooped up everything from cattle sized hypodermic needles to razor blades in popular beaches. Probably the most common hazard I scoop out is rusted jagged flakes of metal from shipwrecks. That stuff washes in with every storm and change in the current. It's thin and light and sharp as hell and mixes right in with the soft pretty sand.

    After doing this a few years I never go barefoot at the beach.

    .
     
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  33. Scorpio

    Scorpio Скорпион Founding Member Board Elder Site Mgr Site Supporter ++

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  34. Scorpio

    Scorpio Скорпион Founding Member Board Elder Site Mgr Site Supporter ++

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    Representation of Earth's Invisible Magnetic Field
    [​IMG]
    Schematic illustration of the invisible magnetic field lines generated by the Earth, represented as a dipole magnet field. In actuality, our magnetic shield is squeezed in closer to Earth on the Sun-facing side and extremely elongated on the night-side due to the solar wind.

    Earth's polarity is not a constant. Unlike a classic bar magnet, the matter governing Earth's magnetic field moves around. Geophysicists are pretty sure that the reason Earth has a magnetic field is because its solid iron core is surrounded by a fluid ocean of hot, liquid metal. The flow of liquid iron in Earth's core creates electric currents, which in turn creates the magnetic field. Credit/Copyright: Peter Reid, The University of Edinburgh
     
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  35. GOLDBRIX

    GOLDBRIX God,Donald Trump,most in GIM2 I Trust. OTHERS-meh Site Supporter Platinum Bling

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    A Definition of FAITH
     
  36. Mujahideen

    Mujahideen Black Member Midas Member

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    And I think the core is solid due to the gravitational pressure.
     
  37. Scorpio

    Scorpio Скорпион Founding Member Board Elder Site Mgr Site Supporter ++

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    if we allow a solid core surrounded by molten fluid, then this is a rough explanation


    How do you find the pressure in a fluid?
    A solid surface can exert pressure, but fluids (i.e. liquids or gases) can also exert pressure. This might seem strange if you think about it because it's hard to imagine hammering in a nail with liquid. To make sense of this, imagine being submerged to some depth in water. The water above you would be pushing down on you because of the force of gravity and would therefore be exerting pressure on you. If you go deeper, there will be more water above you, so the weight and pressure from the water would increase too.
    Not only can the weight of liquids exert pressure, the weight of gases can as well. For instance, the weight of the air in our atmosphere is substantial and we're almost always at the bottom of it. The pressure exerted on your body by the weight of the atmosphere is surprisingly large. The reason you don't notice it is because the atmospheric pressure is always there. We only notice a change in pressure above or below normal atmospheric pressure (like when we fly in an airplane or go underwater in a pool). We aren't harmed by the large atmospheric pressure because our body is able to exert a force outward to balance the air pressure inward. But this means that if you were to be thrown into the vacuum of outer space by space pirates, your body pressure would continue pushing out with a large force, yet no air would be pushing in.

    [So would you blow up?]

    You probably wouldn't blow up since your body/skin/bones are strong enough to hold you together. Still, it would be really, really uncomfortable. Besides the lack of oxygen and possible direct radiation exposure from the sun, your eyes would bulge, your eardrums could pop, and the saliva on your tongue would probably boil since the boiling point of water decreases as pressure goes down. At zero pressure your body temperature is enough to boil the water on your tongue as well as the fluid in your eyes. So basically, don't ever get caught by space pirates.

    Okay, so the weight of a fluid can exert pressure on objects submerged in them, but how can we determine exactly how much pressure a fluid will exert? Consider a can of beans that got dropped in a pool as seen in the following diagram.

    [Who dropped the beans?]

    This is one of the great mysteries of the universe. I doubt we will ever know. If you find out, please contact the Department of Physics Mysteries immediately.
    [​IMG]
    A can of beans submerged below the water to a depth h.

    The weight of the column of water above the can of beans is creating pressure at the top of the can. To figure out an expression for the pressure we'll start with the definition of pressure.

    P=FA\Large P=\dfrac{F}{A}P=AFP, equals, start fraction, F, divided by, A, end fraction

    For the force FFFF we should plug in the weight of the column of water above the can of beans. The weight is always found with W=mgW=mgW=mgW, equals, m, g, so the weight of the column of water can be written as W=mwgW=m_{w}gW=mwgW, equals, m, start subscript, w, end subscript, g where mwm_wmwm, start subscript, w, end subscript is the mass of the water column above the beans. We'll plug this into the equation for pressure above and get,

    P=mwgAP=\dfrac{m_w g}{A}P=AmwgP, equals, start fraction, m, start subscript, w, end subscript, g, divided by, A, end fraction

    At this point it might not be obvious what to do, but we can simplify this expression by writing mwm_wmwm, start subscript, w, end subscript in terms of the density and volume of the water. Since density equals mass per volume ρ=mV\rho=\dfrac{m}{V}ρ=Vmrho, equals, start fraction, m, divided by, V, end fraction , we can solve this for the mass of the water column and write mw=ρwVwm_w=\rho_w V_wmw=ρwVwm, start subscript, w, end subscript, equals, rho, start subscript, w, end subscript, V, start subscript, w, end subscript where ρw\rho_wρwrho, start subscript, w, end subscript is the density of the water and VwV_wVwV, start subscript, w, end subscript is the volume of the water column above the can (not the entire volume of the pool). Plugging in mw=ρwVwm_w=\rho_w V_wmw=ρwVwm, start subscript, w, end subscript, equals, rho, start subscript, w, end subscript, V, start subscript, w, end subscript for the mass of the water column into the previous equation we get,

    P=ρwVwgA P=\dfrac{\rho_w V_wg}{A}P=AρwVwgP, equals, start fraction, rho, start subscript, w, end subscript, V, start subscript, w, end subscript, g, divided by, A, end fraction

    At first glance this appears to have only made the formula more complex, but something magical is about to happen. We have volume in the numerator, and area in the denominator so we're going to try and cancel something here to simplify things. We know that the volume of a cylinder is Vw=AhV_w=AhVw=AhV, start subscript, w, end subscript, equals, A, h where AAAA is the area of the base of the cylinder and hhhh is the height of the cylinder. We can plug in Vw=AhV_w=AhVw=AhV, start subscript, w, end subscript, equals, A, h for the volume of water into the previous equation and cancel the areas to get,

    P=ρw(Ah)gA=ρwhgP=\dfrac{\rho_w (Ah)g}{A} = \rho_w h gP=Aρw(Ah)g=ρwhgP, equals, start fraction, rho, start subscript, w, end subscript, left parenthesis, A, h, right parenthesis, g, divided by, A, end fraction, equals, rho, start subscript, w, end subscript, h, g

    [Are we sure the areas cancel?]

    Good question. The original area AAAA in the denominator was the area upon which the force is exerted, which was the area of the top of the can. The area AAAA in the numerator refers to the area of the column of water. Since the area of the column of water is equal to the area of the top of the can, these areas do in fact cancel.

    Not only did we cancel the areas, we created a formula that only depends on the density of the water ρw\rho_wρwrho, start subscript, w, end subscript, the depth below the water hhhh, and the magnitude of the acceleration due to gravity gggg. This is really nice since nowhere does it depend on the area, volume, or mass of the can of beans. In fact, this formula doesn't depend on anything about the can of beans other than the depth it is below the surface of the fluid. So this formula would work equally well for any object in any liquid. Or, you could use it to find the pressure at a specific depth in a liquid without speaking of any object being submerged at all. You'll often see this formula with the hhhh and the gggg swapping places like this,
    P=ρgh{\Large P= \rho gh}P=ρghP, equals, rho, g, h

    Just to be clear here, ρ\rhoρrho is always talking about the density of the fluid causing the pressure, not the density of the object submerged in the fluid. The hhhh is talking about the depth in the fluid, so even though it will be "below" the surface of fluid we plug in a positive number. And the gggg is the magnitude of the acceleration due to gravity which is +9.8ms2+9.8 \dfrac{\text{m}}{\text{s}^2}+9.8s2mplus, 9, point, 8, start fraction, m, divided by, s, start superscript, 2, end superscript, end fraction .

    Now you might think, "OK, so the weight of the water and pressure on the top of the can of beans will push the can downward right?" That's true, but it's only a half truth. It turns out that not only does the force from water pressure push down on the top of the can, the water pressure actually causes a force that pushes inward on the can from all directions. The overall effect of the water pressure is not to force the can downward. The water pressure actually tries to crush the can from all directions as seen in the diagram below.

    [Wait, but ...]

    OK, if you are really clever you might have realized that the bottom of the can is slightly lower in the fluid than the top of the can, and since the pressure gets larger the deeper you go (Pgauge=ρghP_{gauge}=\rho g hPgauge=ρghP, start subscript, g, a, u, g, e, end subscript, equals, rho, g, h) the upward pressure on the bottom of the can should be slightly larger than the downward pressure on the top of the can. This means that the overall effect of the pressure from the water is to crush the can and to exert a net upward force on it. This net upward force from the difference in pressure is the reason why there's a buoyant force on objects submerged in a fluid! But...we're getting a little ahead of ourselves so let's hold this thought for now.
    [​IMG]
    A can of beans being squeezed by water pressure.

    If it helps, you can think about it this way. When the can of beans fell into the water, it quite rudely displaced a large amount of water molecules from the region where the can is now. This caused the entire water level to rise. But water is pulled down by gravity which makes it want to try and find the lowest level possible. So the water tries to force itself back into the region of volume that it was displaced from in an effort to try and lower the overall height of the body of water. So, whether a can of beans (or any other object) is in the water or not, the water molecules are always being squashed into each other from the force of gravity as they try to lower the water level to the lowest point possible. The pressure PPPP in the formula ρgh\rho ghρghrho, g, h is a scalar that tells you the amount of this squashing force per unit area in a fluid.

    [Hold on. Pressure is a scalar?!]

    OK, so here is a subtle fact about pressure; it's defined to be a scalar, not a vector. So why do people seem to represent pressure in diagrams with arrows as if it were a vector with a particular direction?

    Even though pressure is not a vector and has no direction in and of itself, the force exerted by the pressure on the surface of a particular object is a vector. So when people draw diagrams with pressure pointing in specific directions, those arrows can be thought of as representative of the direction of the forces on those surfaces exerted by the pressure from the fluid.

    If there were no surface upon which the pressure could exert a force, it would make no sense to draw a direction for the force at that point inside the water. On the left hand side of the diagram below there are water molecules and pressure, but no well defined direction of force. The right hand side of the diagram below shows the well defined directions of forces on an ice cream cone submerged in the water.

    While we're on the topic, we might as well make it clear that the force exerted on a surface by fluid pressure is always directed inwards and perpendicular (at a right angle) to the surface.
    [​IMG]
    At this point, if you've been paying close attention you might wonder "Hey, there's air above the water right? Shouldn't the weight of the column of air above the column of water also contribute to the total pressure at the top of the can of beans?" And you would be correct. The air above the column of water is also pushing down and its weight is surprisingly large.

    [How large?]

    Many people think air has no mass and no weight, but that's not true. The narrow column of air with the same radius as a typical can of beans that stretches from sea level to the top of the atmosphere has a mass of around 30 kg30 \text{ kg}30 kg30, space, k, g (that's like the weight of 30 pineapples). The force from atmospheric pressure on the top of a chessboard would be comparable to the weight of a car.

    You might wonder how we can pick up the chessboard so easily if the weight of a car is pushing down on it, but it's because the weight of a car is also pushing up on it. Remember that the force from fluid pressure does not just push down, it pushes inwards perpendicular to the surface from every direction. It may not seem like there is any air under the chessboard when placed on the table but the roughness and cracks of the chess board are enough to allow air underneath. If you could get rid of all the air underneath the chessboard and prevent air from being allowed to sneak back in, that board would be stuck to the table like a suction cup. In fact, that's how suction cups work. They push the air out to create less pressure inside than out. The smooth plastic of the suction cup prevents air from sneaking back in. The higher pressure outside air pushes the suction cup into the surface. (see the diagram below)
    [​IMG]
    Once air sneaks back in, the inside pressure becomes the same as the outside pressure and the cup can easily be taken off the surface.

    If you wanted a formula for the total pressure (also called absolute pressure) at the top of the can of beans you would have to add the pressure from the Earth's atmosphere PatmP_{atm}PatmP, start subscript, a, t, m, end subscript to the pressure from the liquid ρgh\rho ghρghrho, g, h.

    Ptotal=ρgh+Patm{\Large P_{total}=\rho gh +P_{atm}}Ptotal=ρgh+PatmP, start subscript, t, o, t, a, l, end subscript, equals, rho, g, h, plus, P, start subscript, a, t, m, end subscript

    We typically don't try to derive a fancy term like ρairgh\rho_{air} g hρairghrho, start subscript, a, i, r, end subscript, g, h for the atmospheric pressure PatmP_{atm}PatmP, start subscript, a, t, m, end subscript since our depth in the Earth's atmosphere is pretty much constant for any measurements made near land.

    [Why else don't we use it?]

    A problem with trying to use ρairgh\rho_{air} ghρairghrho, start subscript, a, i, r, end subscript, g, h to find the pressure at a certain depth in the atmosphere is that unlike the water example, the density of the air in the atmosphere is not the same at all altitudes. As you go higher in the atmosphere the density of air decreases so we can't treat ρair\rho_{air}ρairrho, start subscript, a, i, r, end subscript as a constant.

    This means that the atmospheric pressure at the surface of the Earth stays relatively constant. The value of the atmospheric pressure at the surface of the Earth is stuck right around 1.01×105Pa1.01 \times10^5 Pa1.01×105Pa1, point, 01, times, 10, start superscript, 5, end superscript, P, a. There are small fluctuations around this number caused by variations in weather patterns, humidity, altitude, etc., but for the most part when doing physics calculations we just assume that this number is a constant and stays fixed. This means, as long as the fluid you're finding the pressure for is near the surface of the Earth and exposed to the atmosphere (not in some sort of vacuum chamber) you can find the total pressure (also called absolute pressure) with this formula.

    Ptotal=ρgh+1.01×105Pa P_{total}= \rho gh +1.01 \times 10^5 PaPtotal=ρgh+1.01×105PaP, start subscript, t, o, t, a, l, end subscript, equals, rho, g, h, plus, 1, point, 01, times, 10, start superscript, 5, end superscript, P, a

    [I don't understand this equation.]

    The ρgh\rho ghρghrho, g, h corresponds to the pressure
     
  38. Bottom Feeder

    Bottom Feeder Hypophthalmichthys molitrix Gold Chaser Site Supporter

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    Well. That should settle that!
    Scorpio, yer funny.

    BF
     
  39. Scorpio

    Scorpio Скорпион Founding Member Board Elder Site Mgr Site Supporter ++

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    what one might see as a random point, but what the heck right? We is just talkin'

    how much of the heat from the core is what makes the surface life cycle what it is?
    we have the supposed protective envelope of gasses surrounding the earth, protecting us from the cold of space, in addition to the added heat of sun energy then trapped by those protective gasses.

    which then begs the question, how much of internal earth activity, at the cores, directly impacts surface temp and effects?

    ie all this nattering on about global warming, global cooling, man made this or that, etc.

    what if these cycles were due to solar activity and the action at the earths core?

    if that massive field of molten carbon is sitting just under the us of friggin' a, those few cars tramping around on the surface are but a molehill on a mountain in regards to co2 generation.
     
  40. Scorpio

    Scorpio Скорпион Founding Member Board Elder Site Mgr Site Supporter ++

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    I could have made that 'can of worms' for ya

    :beer:
     
    Bottom Feeder likes this.

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