Recent content by NEGATIVE_40

I have a function Z = f(P,T) and would like to calculate the partial differentials \left ( \frac{\partial Z}{\partial P} \right )_T and \left ( \frac{\partial Z}{\partial T} \right )_P at values of P and T. The function Z is compressibility factor (Lee and Kessler equation of state), P...

Are you referring to the correct one given by my textbook? \vec{K}=\vec{j}cos(\gamma)+\vec{k}sin(\gamma) if gamma = 0 , then the axis xyz would be lined up so y corresponded to Z. That's exactly what the diagram is saying, so I don't see a problem with that. It's just how the textbook has...

Just thinking about this, how do I know which way I should have the triangle going? For example, in the diagram I've attached, I have the 90 degree angle on the Y-axis. To get the answer it appears I should just do the opposite (always have 90 degree angle NOT on the IJK axes or parallel to...

Homework Statement *see attachment for diagram* I'm having trouble understanding a step in an example problem. "The Z-axis is vertical and carries the unit vector \vec{K}=\vec{j}cos(\gamma)+\vec{k}sin(\gamma) " is what I cannot understand. The Attempt at a Solution I want...

so I need to be doing the CHANGE in height from the equilibrium position to some displaced position? I thought you only needed the potential AT the displaced position, ie you don't care about where it ends up only where its at when you do the energy stuff? I think why I was confused with...

hey guys, I have a question regarding how to get the potential energy for this. I can get the correct answer, but the solutions do a step that makes absolutely no sense to me, so hopefully someone leads me in the right direction :smile: Homework Statement Using energy method, derive the...

yep. so it isn't a multiple of the homogenous solution. I did a course of DE's a while ago, I just forgot what to do in this case.

[tex] y_p = A [tex] so doing that I get A = 0.21, which gives me the correct solution. thanks.

Homework Statement y''+16y=3.36 This is actually part of a spring question I'm attempting at the moment, and I'm having a mental blank on how to deal with the 3.36.Homework Equations n/a The Attempt at a Solution I've found the characteristic equation and solution based from that; c_1...

Okay it all works out now. I had to add, not subtract, the radii for the MOI in the circular section. :smile: Thanks.

thanks for your reply. for the cylindrical portions I'm now using the MOI of a circular cylinder of length L about z axis (as I have the axis set up, z coming out of the page) I_z= \frac{1}{2}m(R_{Bo}^2-R_{Bi}^2) which is actually the same as that of a thin disk. The difference would be...

Homework Statement What is the radius of gyration (in meters) for the steel flywheel shown? The width of its rim, L, is as given below. The density of steel is 7500 kg/m3. The outside diameter (OD)for the wheel is 2000 mm, and the inside diameter (ID) is 1840 mm as shown in the figure. The...

You seem to have made a mistake in the step (A-2I)\vec{v}=\vec{0} Why is your second row 1 0 1 instead of 0 0 1 ? Have you said v_2= \delta ? I'm not sure if I have read that correctly. If it is a delta, you can't say that unless the whole row equals zero. i.e. \begin{bmatrix} 0 & 0 &...

I get the same result as your teacher for \lambda = 2 A= \begin{bmatrix} 3 & 1 & 0\\ 0 & 2 & 1\\ 1 & 1 & 3 \end{bmatrix} so for lamda = 2, (A-2I)\vec{v}=\vec{0} \begin{bmatrix} 1 & 1 & 0\\ 0 & 0 & 1\\ 1 & 1 & 1 \end{bmatrix} \begin{bmatrix} v_1\\ v_2\\ v_3...

Just to makes things clear, this is what I have done. \delta_{A/C}= \sum \frac{PL}{EA}= \frac{P_{AB}L_{AB}}{EA}+ \frac{P_{BC}L_{BC}}{EA}= \frac{-42000N \cdot 0.4m}{200\times 10^9Pa \cdot (\frac{\pi}{4}\cdot 0.03^2)} + \frac{-90000N \cdot 0.6m}{200\times 10^9Pa \cdot (\frac{\pi}{4}\cdot...