Recent content by ForTheGreater

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    Conversion vectors in cylindrical to cartesian coordinates

    Thank you, I think I just didn't think of that you'll need both the Ax component and the Ay component of the vector to get the x coordinate.
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    Conversion vectors in cylindrical to cartesian coordinates

    If I have a point r=4, phi=pi/8 and z=z; in cylindrical coordinates. sqrt( (r*cos(phi) )2 + (r*sin(phi) )2 ) = 4 So taking r*cos(phi) as the x component and r*sin(phi) as the y component seems to be enough to get the same point represented in both coordinate systems? What am I missing?
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    Conversion vectors in cylindrical to cartesian coordinates

    Homework Statement It's just an example in the textbook. A vector in cylindrical coordinates. A=arAr+aΦAΦ+azAz to be expressed in cartesian coordinates. Start with the Ax component: Ax=A⋅ax=Arar⋅ax+AΦaΦ⋅ax ar⋅ax=cosΦ aΦ⋅ax=-sinΦ Ax=ArcosΦ - AΦsinΦ Looking at a figure of the unit vectors I...
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    Chemical Bonds - various questions

    A group 2 metal always forms 2+ ions, since the second electron is harder to remove how come you don't find 1+ ions of these in ionic compound formations, How does it always manage to lose both outer electrons? So it takes a certain amount of energy to break a bond, how does water molecules...
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    Velocity fluctuations, variance and moment in turbulence

    Yea I'm sorry I should be consistent with notation. I'm only talking about the fluctuating part. So second moment is really just measure of deviation from the mean and third moment is measure of skewness?
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    Velocity fluctuations, variance and moment in turbulence

    Thank you for your reply. I understand the standard deviation, meaning the root of the second moment. But in the models the second moment is used directly. For example the v3 is skewness and v4 is something else. Now I don't understand how v3 is skewness but I kind of understand what it is. I...
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    How to intuitively see the v^2 relation to kinetic energy?

    Yes, thank you. Funny you should respond today. I was thinking about this again today and I reason as such that momentum is m*v and the rate at which momentum is traveling is (m*v)*v which is kinetic energy. I like the way you put it very much too.
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    Velocity fluctuations, variance and moment in turbulence

    I'm studying CFD and I'm on turbulence. It states that the fluctuating part of velocity squared and time averaged is the variance but variance in statistical terms is the deviation from the mean squared and averaged. So what is variance in turbulent fluctuating velocity? This variance is also...
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    How to intuitively see the v^2 relation to kinetic energy?

    KE is proportional to v^2. In a gravitational field KE=1/2 m*v^2. It's easy to find mathematically Work=Fd=mad=m(v/t)(v*t)=m*v^2. But how to visualize it or get an intuitively "feel" for this v^2 relationship?
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    Electric Potential of charged isolated body.

    2V and 2U. I should have stated that with no charge both potentials is zero. I don't see your point. The anser is V_A = U (√ 5 +1)/2
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    Electric Potential of charged isolated body.

    Homework Statement Two equal isolated metallic bodies A & B start with no charge and zero potential. A is given a charge giving B the potential U. B is then Grounded giving A the potential U. What potential did A have before B was grounded? Hint: Use symmetry and use potential coefficients...
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    Linear Interpolation for Given Function

    I have the answer here, it wasn't in the problem. I'm suppose to give the interpolant in all intervals, or as you put it connect the dots. Thank you!
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    Linear Interpolation for Given Function

    Decide the linear interpolant f(-pi)=4 f(-pi/2)=5/4 f(0)=1 f(pi/2)=-3/4 f(pi)=0 the function is (1/pi2 ) (x-pi)2 - cos2 (x-pi/2) Don't know how to do this. I tried lagrange basis functions f(x0)(x1-x)/(x1-x0)+f(x1)(x-x0)/(x1-x0) But it doesn't turn out right. The answer for the first...
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    Electron microscope particle relativistic mass

    I was thinking γm0=mrel? So (qV/m0c2+1)m0=mrel? From where do I get the v to answer b?
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