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    Navier Stokes Equation Derivation and Inertial Forces

    Not sure if I understand exactly what you mean, but if a volume element is size b*dx*dy (= dV), then mass m = rho*dV. Acceleration is nothing but the change in velocity, so ax = du/dx. A force Fx = m*ax = b*dx*dy*du/dx. Perhaps it is good to keep in mind that the Navier-Stokes equation is...
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    Fourier transform

    Substitute the definition of g(t) in the Fourier integral and try putting the exponentials together. You'll probably see it then. ;-)
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    Correct differentiation identity? (tensors, vectors)

    Hello, I'm working on some problems and I want to pose the following, though I am not completely sure it is correct. Can somebody point me to some sources on this? I have tried googling myself, but I only found differentiation identities with either just vectors and scalars on the on hand, or...
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    Cayley Hamilton Theorem

    Hey matqkks, I have come across the Cayley-Hamilton theorem in a college rheology class. Rheology is basically the study of material behaviour, and so rheologists look for equations that can describe materials. Elastic solids are simple in this regard, and can be with a linear relationship...
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    Electromagnetic radiation prevalence

    Thank you for your reply. I asked this questions because I was thinking of the human eye, and how it can only detect a small slice in the electromagnetic spectrum. First I thought this had to mean we are blind to most em-radiation, but upon second thought I realized I also need to know how...
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    Electromagnetic radiation prevalence

    Hello, Perhaps my wording is a bit off so excuse me for that. I think it best to explain by way of a thought experiment. Say there is a device that counts the amount of photons with the same wavelength for all possible wavelengths. What is then the intensity vs. wavelength curve that I would...