Recent content by dcnairb

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    Differential equation for a rocket

    You could divide by ## -u - \frac{b}{k} v## and also by ##m## and then multiply by ##dm## to get $$\frac{dv}{-u - \frac{b}{k} v} = \frac{dm}{m}$$ This is solvable, see if it gets you the answer you need--I feel like both terms' logarithmic solutions would cancel but because of the coefficients...
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    Calculating magnetic moment given magnetization

    Homework Statement Consider a square slab of magnetized material with sides ##2a##, and thickness ##d##, as shown. The magnetization is not uniform: $$M = M_o cos(\frac{2πx}{ a}) \hat{z} $$b) Calculate the total magnetic moment of this object. How would you guess the magnetic field decreases...
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    Electrostatics Fourier Decomposition (problem setting up boundaries)

    I wasn't sure if the uniqueness theorem applied here. Usually you solve for all but one boundary condition and then do a Fourier sum to find one that satisfies all boundary conditions--is that sum the unique solution? As for the incorrect constant, I see what you mean: I have ##C_x = k^2##...
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    Electrostatics Fourier Decomposition (problem setting up boundaries)

    I think an easy to see answer (that I worked out explicitly, even using the orthogonality method of finding ##C_n## just to be sure) I got $$V(x,y,z)=V_o \frac{sinh(\frac{- \pi (b+c) x}{bc})}{sinh(\frac{- \pi (b+c) a}{bc})} sin(\frac{\pi y}{b}) sin(\frac{\pi z}{c})$$ which like I said is pretty...
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    Electrostatics Fourier Decomposition (problem setting up boundaries)

    Well, kind of. I already know how to solve for every form of ##X(x), Y(y), Z(z)## but my trouble is discerning how I can get rid of certain combinations of ##V(x,y,z)=XYZ##. There are 27 total combinations, but the constant equation limits to I think 18. I was hoping I could reason, "well, we...
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    Electrostatics Fourier Decomposition (problem setting up boundaries)

    Sorry about the formatting, my post seems unable to be edited now. Boundaries:All faces $$V=0$$ except for $$V(a,y,z)=V_o sin(\frac{\pi y}{b}) sin(\frac{\pi z}{c})$$ at x=a Dimensions: ##a*b*c## Relevant Equations: ##\frac{X''}{X} + \frac{Y''}{Y} + \frac{Z''}{Z }= 0## implies ##C_x + C_y...
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    Electrostatics Fourier Decomposition (problem setting up boundaries)

    Homework Statement An #a*b*c box is given in x,y,z (so it's length #a along the x axis, etc.). Every face is kept at #V=0 except for the face at #x=a , which is kept at #V(a,y,z)=V_o*sin(pi*y/b)*sin(pi*z/c). We are to, "solve for all possible configurations of the box's potential" Homework...
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    Electrostatics Boundary Conditions (finding potential)

    I thought so, so it all worked out--the potential is 0 everywhere outside of the sphere, and I was able to prove the image charge use by plugging in all points on the radius to show the terms cancel, so I believe I've solved it completely. Thank you very much for the help!
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    Electrostatics Boundary Conditions (finding potential)

    Is infinity considered the other bound of the volume outside of the sphere? I'm not sure if it should be zero or finite at infinity--both are satisfied anyways.
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    Electrostatics Boundary Conditions (finding potential)

    For my outside solution, I tried using Laplace's eqn. coupled with: V=0 everywhere on the shell and rho = 0 everywhere outside of the shell. I got a solution of form ##V = -C/r + D## (because there is no angular dependence) and I'm assuming that the -C/r term comes from the point charge, so...
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    Electrostatics Boundary Conditions (finding potential)

    Homework Statement I have a hollow, grounded, conducting sphere of radius R, inside of which is a point charge q lying distance a from the center, such that a<R. The problem claims, "There are no other charges besides q and what is needed on the sphere to satisfy the boundary condition". I...
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