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You are considering an object (cannonball) of mass $m$. Once it is launched at speed $v$ at an angle $\theta$ from the horizontal direction, the cannonball feels only one force, its own weight $m\vec g$. $g$ is the gravity acceleration ($g\simeq9.81\,\mathrm{m.s^{-2}}$). Newton's equations state that $m\ddot{\vec r}=m\vec g$. The mass can be removed from ...

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The more precisely the position is determined, the less precisely the momentum is known in this instant, and vice versa. --Heisenberg, uncertainty paper, 1927 On the macro level (stuff we can see and touch) it is easy to make these predictions, that is what mechanical engineers do. However, as you get to the atomic and sub-atomic levels, the predictions ...

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1) I think soft-body dynamics is what you're looking for: http://en.wikipedia.org/wiki/Soft_body_dynamics

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From your description I deduce that approximation of geometrical acoustics should be enough. For its applicability we need to ensure that The sound could be described as small perturbation (so, no nonlinear effects). Wavelengths of sound are much smaller than the dimensions of structures with which the sound interacts. The main equation for geometrical ...

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The exact answer can easily be computed by solving the elastic wave equation using the finite-difference time-domain method. You mentioned the image and ray-tracing methods for room acoustics. Theses are geometric methods, which would not be useful for solids since there would need to be separate rays to describe the compressional and shear waves, and the ...

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OpenMC (github) The OpenMC project aims to provide a fully-featured Monte Carlo particle transport code based on modern methods. It is a constructive solid geometry, continuous-energy transport code that uses ACE format cross sections. The project started under the Computational Reactor Physics Group at MIT. You can find more background information in ...

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You should be using the coefficient for the metal in the heat sink. The thermal paste is there simply to close a gap between the two surfaces. With a gap you have to worry about extreme inefficiency between the junction of the two surfaces. The thermal paste isn't perfect and there is still some efficiency loss in the interface but you should probably ...

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First of all, you need to know what $\vec{M}$ is, which is a problem! Secondly, you are doing a volume integral, but if $m$ is constant, then from the point of view of the microscopic currents that create the dipoles, only the boundary or surface currents actually contribute (if you draw a lot of directed square loops on a piece of paper, you will see that ...

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