Recent content by eddiechai2003

Hello Count Iblis, I tried your solution, but it doesn't converge if I randomly choose the value of x_{0}. What are the conditions for convergence? And how to 'find' the proper x_{0}? Thanks.

Homework Statement Is there an iterative method to calculate an inverse of a large matrix faster than a direct method (like Gaussian elimination, or inverse of LU, etc...) ? Homework Equations The Attempt at a Solution I tried the Gauss-Seidel iterative method to inverse a...

Homework Statement Does anyone know the inverse of sinc(x) or \frac{sin(x)}{x}? Homework Equations If sinc(x)=a, x=f(a). What is x in function of a? The Attempt at a Solution If I knew the exact value of a, I could find the corresponding value of x graphically. But how do I find...

It seems like I have messed somethings up. There are 2 different kinds of spring constant. Say k_L for linear springs (compression and extension) and, say k_T, for torsion springs. [k_L]=[\frac{Force}{Length}] while [k_T]=[\frac{Force\times Length}{Radian}]. So, mohlam12, your solution...

Hello, After working for a few hours, I come out with a solution which is "dimensionally" correct. However, I am still not very convinced about the exactitude of the solution since I don't know much about the spiral spring and I couldn't find much information about it on the internet. Below...

Hello mohlam12, Your solution is: \ddot{\theta}{+\frac{\mu}{l}.\theta-\gamma.sin(\theta)=0} It seems to me correct but I have doubt since the dimension is not homogeneous. {[\frac{\mu}{l}]\neq[\gamma]} (\theta and {sin(\theta)} are dimensionless) I will recheck your solution...

Hello mohlam12, The french version of the question: Une tige sans masse de longueur {l}, est fixée en {O} sur un axe. On note \theta l'angle formé par la tige et la verticale montante. Un ressort en spiral est fixé entre l'axe et la tige de telle façon qu'au repos (\theta{=0}) la tige soit...

Hello HallsofIvy, Actually, the original question was not in english. I translated it from french version and I am sure it is slightly different from the original question since I didn't totally understand the notion of moment or driving moment (according to wikipedia). Maybe you know better...

Homework Statement http://chokleong.com/ESIEE/images/system.png [/URL] A stick, whose mass is neglected, with length {l} is fixed at point {O} on a vertical axis. \theta is the angle formed between the stick and the vertical axis. A spiral spring is attached to the vertical axis and the stick...