Recent content by paxprobellum

I'm having a wording issue in a paper I'm writing. Specifically, I'm trying to decide between arguing something is "diffusion" vs. "dispersion". Can anyone point me to a reference that clearly demarcates between these? In specific, I'm referring to the diffusion/dispersion of an injected drug...

I have decided a game plan: Try to solve cos(theta) = dot(B'D', A'C') / |B'D'|*|A'C'| I have solved for |A'C'| already. I think I can solve for |B'D'| without much difficulty. Then I need to determine the direction cosines for B'D' and A'C'. Finally, plug in and solve. Still fishing for...

Part A: Check out example 3 on http://www.mathworks.com/access/helpdesk_r13/help/techdoc/ref/fzero.html You are supposed to write "f.m" for this problem. Part B: The MATLAB function fzero finds zero points for a function with a single variable. One could imagine: [1] V/V0 = f(x) where V is...

Ah, I had some insight. So the reason its not a right angle anymore is because C' is farther away from C than A' is from A. (The midpoint of AC has moved closer to C!) Still kinda lost about how to use this information though.

Homework Statement Strain tensor E = [0.02 0 0; 0 0.01 0; 0 0 0.03] (no shear strains). A triangle consists of points A, B, and C, each on axis X1, X2, and X3 respectively. The lengths OA = OB = OC, and D is the midpoint of AC. The direction cosines of AC are (1/sqrt(2), 0, -1/sqrt(2)) and...

The applied axial load does shift the neutral axis. Consider it qualitatively -- pure bending produces compression on one side, tension on the other, and the neutral axis at the midpoint of the beam. If you apply a compressive load on top of that, tensile stress less than the compressive load...

See: see: https://www.physicsforums.com/showthread.php?p=2314761 Homework Statement Consider a hollow beam of length L where a force F is applied in compression at the bottom of the beam. (An off-center axial point load.) Determine the stress at the top and bottom of the beam at x=L/2. The...

It looks like you dropped a 7 in your determinant calculation. I got: f(x) = -x^3 + 7*x^2 - 3*x -1 so f(A) = ?

Thanks ;)

Yes. The moment is produced due to the lever arm. I suppose the lever arm appears as the force drifts from the center. So the lever arm must be the distance to the center of the beam, or half the thickness. Good?

Homework Statement Consider a cantilever beam of length L where a force F is applied in compression at the bottom of the beam. (An off-center axial point load.) Determine the stress at the top and bottom of the beam at x=L/2. Homework Equations There is both compressive and bending...

Something is not right here. if you multiply your first equation by 5, you get: 5 = 10C + 5E but your last equation is: 5 = 10C + 2E So which is it? I think you may have made a mistake somewhere coming up with these equations.

Well, I don't know if this qualifies as a "transformation" -- again, welcoming comments.

Excellent idea! I didn't think the constant could be solved for. I did: I(0,t) = \int _{0}^{Inf} e^{-kw^{2}t} dw = \frac {1}{2} [\frac {\pi}{kt}] ^{(1/2)} = C Thanks again for your help. I am struggling on this problem set for some reason (see my other "talk to myself" post :P)...

So it turns out that the substitution is a = t(K-G). Thus you can take the integral offline by evaluating the resultant Gaussian. Thanks! At least PF let's me talk to myself better :P