Recent content by etothey

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    Is the Invariance of Physical Laws Linked to a Symmetry Group Structure?

    Homework Statement The invariance of physical laws to a coordinate change suggests a symmetry group structure. Can the operations of cordinate transformation be written as group operations? What is the group? Homework Equations The Attempt at a Solution At the moment I do not...
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    Invariance of vectors due to changes in coordinate systems

    Homework Statement How do I know that vector is invariant to changes of coordinate systems if i only have the components of the vector and not the basis vectors? Homework Equations let the vector in reference frame 1 be ds and the same vector in the reference frame 2 be ds1 The...
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    Solving Pascals Principle for Hydraulic Jack - F2 = 10.8N

    anyone?
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    "Calculate Resultant Force on Vertical Dam Wall

    anyone?
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    Calculating Pressure Difference in Two Tanks

    anyone?
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    Solving Pascals Principle for Hydraulic Jack - F2 = 10.8N

    Homework Statement A hydraulic jack has the dimensions as shown in the figure to the left. A force F of 120 N is exerted on the handle of the jack. What load, F2, is being supported by the jack? Homework Equations P1=P2 P=F/A The Attempt at a Solution I know that P1=P2 And P2 =...
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    "Calculate Resultant Force on Vertical Dam Wall

    Aha, I see. This is first fluid question I had involving integration. Thus, I integrated \intPo + pgh dh from 0 to H. Getting P=PaH + pgH^2/2. Thus PA = HW(PaH + pgH^2/2). Better now?
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    Calculating Pressure Difference in Two Tanks

    Homework Statement Two tanks, one containing SAE Grade 30 oil (density of 890 kg/m3) and the other containing carbon tetrachloride (density of 1,590 kg/m3) , are connected through a differential manometer as shown in the figure. Calculate the pressure difference between chambers A and B...
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    "Calculate Resultant Force on Vertical Dam Wall

    Homework Statement Pressure_2.jpg: http://www.imageupload.org/thumb/thumb_8609.jpg A vertical dam wall has a width w. Water is filled to a height H behind the dam. Calculate the resultant force on the dam wall. Homework Equations P=F/A P= Pa + p*g*h The Attempt at a...
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    Equation of continuity of water depth

    Thank you very much!
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    Equation of continuity of water depth

    sexy!
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    What is the constant density of a solid sphere given its radius and mass?

    Homework Statement The density of a solid sphere of radius R=10cm and mass M=15kg varies with distance from the center according to the equation p=po*e^(r/R). Determine the constant po. Homework Equations density= mass over volume. The Attempt at a Solution Change density to...
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    Equation of continuity of water depth

    Homework Statement A can of height h and cross-sectional Area Ao is initially full of water. A small hole of area A1<<Ao is cut in the bottom of the can. Find an expression for the time it takes all the water to drain from the Can. Hint: Call the water depth y use the continuity equation to...
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    Fermat's Principle: Proving Law of Reflection

    Homework Statement Fermat’s principle states that the path of a light ray between two points is such that the time to traverse that path is an extremum (either a minimum or a maximum) when compared with the times for nearby paths. Consider two points A and B on the same side of a reflecting...
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    Solving a Balloon Mass Calculation: Find Minimum Gas Mass Needed

    Managed to solve it. Thanks!