Recent content by arestes

Hi! thanks. I was thinking of something like that but what I need is the IC when the whole mechanism is vertical. By analyzing it as a limit case I believe the IC of the middle member would be exactly at the joint at the upper end of it. But I can't make sense of it since it would have zero...

haha, yeah, I'm aware of the different conventions for the figures, but it seems to be something of a regional fashion. The notation I gave is found almost everywhere in german universities, probably all across Europe, idk. It's on Wikipedia and books on Statics by german authors, such as...

Hi! First, thanks for the links and animation (may I ask where you found the animated gif? They might come in handy for me). Also, unfortunately, I still can't for the life of me find the ICR for member II and member III. I am supposed to follow the rules to find them but I get a contradiction...

Hi, I'm attaching the convention for figures used in my course and I believe it's common in many countries for Engineering: They only have one perpendicular reaction, allowing displacement parallel to the wall

Hello I did part 1 of this HW using the rules for findint Instantaneous Center of Rotations in STATICS (Hauptpol in german) and Nebenpol (idk how to translate it). I attached my calculation and it's supposed to be the right answer. I replaced the two forces on A (piston force Ah and vertical...

Sure, I am attaching two images (the one on the left is the one I was talking about). I drew the infinitesimal movements as a displacement du and angular displacements dphi1 dphi2. I guess it's right but only intuitively... but what I'm trying to figure out is the answers using Inst. Cent. of...

Hello. I understand that plotting the hauptpole (I believe it's called "instantaneous center of rotation" in English) in STATICS is useful for virtual displacements. I know the rules: Hauptpol (ICR, which is denoted (0, #member) ) are located where a support of a member is fixed. For a member...

Yes, the R is due to the transmission line. Oh, thanks for clarifying that impedance matching is not desirable in this case for it would waste half of power. I still have trouble understanding how we can talk about "generated power" if the transmitted power depends upon the load.

Hello: I'm confused about transmission lines. According to Faraday's Law, what's induced is an emf that depends on how fast the coils spin, or whatever equivalent to a simple model seen on Physics textbooks. Power, however, is then assumed constant when talking about the power loss due to...

Summary:: I'm a Physics instructor (no formal Engineering training) in a private college. As part of my job I had to teach Statics and Mechanics of Materials. They now formed a student group to start activities looking to do research and they wanted me as advisor. Hello guys. So basically I...

Yeah but quadratic forms don't have linear terms. Thanks for reminding me of wikipedia. I did find the info I needed (almost) here:https://en.wikipedia.org/wiki/Matrix_representation_of_conic_sections I found that there is a general form to write the equation of a conic (valid for central...

Hello: I'm not sure if there's an accepted canonical form for a quadratic equation in two (or more) variables: $$ax^2+by^2+cxy+dx+ey+f=0$$ Is it the following form? (using the orthogonal matrix Q that diagonalizes the quadratic part): $$ w^TDw+[d \ \ e]w+f=0$$ $$w^TDw+Lw+f=0$$ where $$...

Thanks for the ideas both of you Jason and anuttarasammyak. So this seems to fall into the realm of Principal Values I guess. Not sure if it involves generalized (distribution) functions since there aren't any in the end. I'm gland it doesn't involve analytic continuation. It does bother me that...

Hi! I've computed the integral you mention. It still does not converge (t integration results in $$ \frac{u}{1+u^2} $$ and plugging this into the u integral it diverges logarithmically (a direct change of variables will yield evaluating $$\frac{1}{2} Log(1+u^2)$$ between s and infinity). So...

So, I know the direct definition of the Laplace Transform: $$ \mathcal{L}\{f(t) \} = \int_0^\infty e^{-st}f(t)dt$$ So when I plug in: $$\frac{\cos(t)}{t}$$ I get a divergent integral. however:https://www.wolframalpha.com/input/?i=+Laplace+transform+cos%28t%29%2F%28t%29 is supposed to be the...