Recent content by teeeeee

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    Reaching the Rindler horizon in a finite proper time

    Thanks for your quick reply. Still a couple of things I don't follow... How exactly do you transform from \textbf{r}=(t,1,0,0) to \textbf{R}=(atanh(t), \sqrt{1-t^{2}},0,0) ? And how do you get from the square root expression to the sech-squared term? Thanks for your patience!
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    Reaching the Rindler horizon in a finite proper time

    Hi, I am trying to show that timelike geodesics reach the Rindler horizon (X=0) in a finite proper time. The spacetime line element is ds^{2} = -\frac{g^{2}}{c^{2}}X^{2}dT^{2}+dX^{2}+dY^{2}+dZ^{2} Ive found something helpful here...
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    Lagrangian on a saddle advice?

    Hi, I am trying to obtain a Lagrangian for a particle moving on the surface of a saddle z = x^2 - y^2 I have an added complication that the saddle is rotating with some angular frequency, w, and not sure how to incorporate this rotation into my kinetic and potential terms. This is the...
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    Help with integrating differential equation

    Hi, Could someone help me see how the solution of the equation \frac{1}{\mu} \frac{\partial p}{\partial z} = \frac{1}{\rho} \frac{\partial}{\partial \rho} (\rho \frac{\partial v}{\partial \rho}) is v = \frac{1}{4\mu} \frac{\partial p}{\partial z} \rho^{2} + C_{1}ln(\rho)...
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    Help with integrating differential equation

    Hi, Could someone help me see how the solution of the equation \frac{1}{\mu} \frac{\partial p}{\partial z} = \frac{1}{\rho} \frac{\partial}{\partial \rho} (\rho \frac{\partial v}{\partial \rho}) is v = \frac{1}{4\mu} \frac{\partial p}{\partial z} \rho^{2} + C_{1}ln(\rho) +C_{2} Thank...
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    Help with Hagen-Poiseuille Flow

    Hi I'm trying to derive the velocity profile for Hagen-Poiseuille flow through a pipe. Using cylindrical coordinates (z direction horizontal), I began by applying the Navier-Stokes equations to each coordinate. For z, I got: \frac{1}{\eta} \frac{\partial p}{\partial z} = \frac{1}{\rho}...
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    Determine Scalar Potential Function

    How do I determine if there are 2 different potentials..? All the information I have is in my first post.
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    Determine Scalar Potential Function

    So are F,G and H all zero? Or do I need to include a constant at the end? Or a function of all three variables at the end? Thanks
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    Determine Scalar Potential Function

    I don't understand what you mean..
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    Determine Scalar Potential Function

    Hi, I wonder if someone could help me. I'm trying to find the potential function,\phi, of the field: v = y2z3i + 2xyz3j + 3xy2 z2k So using v = \nabla\phi, I have found: \frac{\partial \phi}{\partial x} = y2z3x + F(y,z) \frac{\partial \phi}{\partial y} = y2z3x + G(x,z)...
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    Question about vectors and dot product.

    Hi, Can someone tell me if: -E dotted with ( A + B ) is equal to -E.A -E.B where E, A and B are all vectors What I mean is, does the minus sign appear on the E.B bit as well? Also, is \int \frac{d}{dt} (A) dV equal to: \frac{d}{dt} \int (A) dV Thank you
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    Help with derivation of euler-lagrange equations

    Hi, I am trying to follow a derivation of the euler lagrange equations in one of my textbooks. It says that \int ( f\frac{dL}{dx} + f'\frac{dL}{dx'}) dt = f\frac{dL}{dx'} + \int f ( \frac{dL}{dx} - \frac{d}{dt}(\frac{dL}{dx'}) ) dt where f is an arbitrary function and L is the...
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    Understanding the Dot Product of Derivatives

    Hi, Im having trouble understanding something in one of my Dynamics lectures. The lecturer said that: dr/dt dotted with d2r/dt2 (where r is a vector) equals: (1/2)(d/dt(dr/dt dotted with dr/dt))... I just can't get this result. I know it has something to do with the product rule...
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