what is a "Straight Gravity Dam"?
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A gravity dam is a dam which stops the water through its weight.\n\nThey are simple to build but are only good for small dams. You just find the location where you want the dam and throw a few million tons of concrete into that area until it's enough to stop the flow of water.\n\n\nAnother type of dam would be an arch dam like Hoover Dam. Instead of using the dam's weight to hold back the water, it's shaped like a horseshoe and is actually wedged against two mountains.
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a) You have to draw gravity as a straight line down. Then you have to realize that gravity does no work if the block was on a horizontal surface. Work done by gravity is alway M*G*H.  The mass is 4.8 kg and the gravity is 9.81 m/s^2 .  The height will be sin (30) = H/2.  the sin (30 degrees) is 0.5 so .5=H/2.  the height will be .5/2 = .25 m.\n\nsoo you will have 4.8*9.81*0.25\n\nb) the work done by the frictional force will always be the frictional force times the distance.  The frictional force is going to be the normal force times Uk.  The normal force has components to it, so its going to be sin(30)*g*m.  The you need to multiply that by the friction coefficient and then by the distance traveled.  You will have 2*0.436*sin(30)*4.8*9.8\n\nc.  The work done by the normal force is just going to be cos(30) (i think) times 2 ( the distance traveled) times 9.81 (gravity) times 4.8 (the mass)
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All dams have various levels of natural strength and safety. All types of dams have also suffered catastrophic failures.\nThe best example I can give you of a concrete dam failure is the St. Francis Dam in southern California, 1928. It was a concrete Gravity Arch dam about 200 feet high. It failed under a full reservior, due to the re-activation of an ancient landslide that composed the dam's left abutment. However, it's twin sister, the Hollywood (Mulholland) Dam, after retrofitting in the early 1930's, has stood strong to this day.\nEarthen dams have also failed, such as the Teton Dam in the 1970's.\nThe Van Norman Dam in the San Fernando Valley (rolled earth fill dam) collapsed during the 1971 Sylmar quake, but didn't fail. It held it's water long enough for emergency crews to lower the water level to a safe point, saving many lives and homes.\nThe biggest safety concerns for concrete dams are:\n1. Is the concrete of sufficient strength, with a well-cleaned aggregate?\n2. Is the foundation sound?\n3. What kind of siesmic activity can be expected in the area?\n4. Are there sufficient seepage galleries and grout curtains to control excess water and prevent piping?\n\nIf you're comparing concrete dam types, I'd say an arch dam is at least as safe as a concrete gravity dam (such as Shasta) provided it has firm rock to brace against.\n\nBasically, a dam is a wall that creates an entire lake behind it. Water is very heavy, and will always try to escape. So, as safe as they try to build them, that safety is always tenuous at best. \nCheck out my website on the St. Francis Dam, at...\nhttp://www.geocities.com/zeebya/integintro.html
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A. to descend it must be less than 600N\nB. Rise to the surface the buoyant factor must be equal to or greater than your 600N.of gravity.\nA buoyancy of equal performance means-Neutral Buoyancy were one can dive or raise with little applied force from the driver.It would be gravity of 600N to buoyancy of 600N applied to counter gravity.
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The Gravity Economy\n\nGravity as a power source is fascinating. It is more abundant than hydrogen, more far reaching than solar power. It exists in dark places with still winds and in climates cold and warm. We've been tapping its power for thousands of years -- through water wheels, dams, and clockwork counter weights.\n\nGeothermal power is a form of gravity power at work. The pressure of the outer earth on its core keeps things hot, rocks and metals, molten. Temperatures can reach 9,000 degrees, almost as hot as the Sun. The original heat may date back to the formation of the earth, which was also the result of gravitational forces. Geothermal power is being used cleanly and successfully in areas where the heat of the earth is relatively easy to tap.\n\nHowever, most of gravity's power comes from devices that use the flow of water. Precipitation conveniently drops water for us in high places in the form of snow and rain, then gravity does the work of transporting it downhill to the sea. Dams and waterwheels are the best known examples. These systems work great and produce no emissions. In fact, by acting on the water of the Columbia River, gravity is powering my computer right now.
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Because of the pressure of water is more at the bottom of the dam. Think of the tonnes of water the dam is holding at the base. \n\nHope this helps...
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A dam holds water in place (hydrostatics, fluid statics)  Hydraulics has more to do with what happens when you change the size of a pipe.
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Up or away from the center of gravity.
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The earth is APPROXIMATELY round due to gravitational forces.
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A dental dam also known as a rubber dam is a material used to isolate a tooth or several teeth for a dental procedure.... most commonly used during a root canal.
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1 foot (12 inches) in a straight line
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In part, specific gravity can be measured with a hydrometer.  You establish a range that the liquid displaces and let it bob until it comes to equalibrium.  This test can be measured at any temperature.  \n\nHowever, mass density is done in a container that is kept at a constant temprature.  The math is easy once the measurments are taken, but there is more time involved in setting up the test and bringing the whole thing to equalibrum
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By the pull of earth's gravity
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Try this website:\n\nhttp://www.screwgravity.com/
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Mentioned before is “the vomit comet”. Actually there is no real way to reach 0 gravity in the close vicinity of any planet. Specifically, you can only have a sensation of “no gravity”.\nOne way to do this is by being inside a system that falls freely – the vomit comet! \nAnother way is by diving. The buoyancy of your body in the water will make you feel like there’s no gravity.\nHowever, with all of these tricks, an accelerometer (any physical device that measures acceleration or force) would alert you to the fact that you are in an accelerating system, or that there is an up-down directionality.
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gravity is stronger, leave it down
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I think I know what you're talking about. It's in California on Highway 1 and it's called the Mystery Spot. \nThe gravity there isn't really off balance, but there is an optical illusion there that makes you think the world is a little crooked.\nThis is thier web site:  http://www.mysteryspot.com/\nI visited there a few years ago, but really was not impressed. Gravity seemed just fine to me.