Hi all! I was trying to figure out how to find the volume of a cone with radius R and height h using integration with cylindrical coordinates. I first tried to set the the integral as:
\int_{0}^{2\pi}\int_{0}^{h}\int_{0}^{R}\rho d\rho dz d\phi
...but I think that this is setting up the...
Okay, my math skills must be low tonight, because I think I got it. :P If someone would confirm what I'm thinking, that'd be nice!
In the end we get that det(A) = (-1)^n*det(A). If n is odd, we get det(A) = -det(A), which is only possible when det(A) is zero. Does that sound right?
Hi all! I was working on some homework for the linear algebra section of my "Math Methods for Physicists" class and was studying skew symmetric matrices. There was a proof I saw on Wikipedia that proves that the determinant of a skew symmetric matrix is zero if the number of rows is an odd...
Thanks for the reply, cepheid! I actually feel really dumb now, because I was picturing the sprocket away from the wheel instead of attached to it. Now the mathematics make total sense, along with the answer. Sorry to have wasted some of your time, but thanks for helping me to know that my...
Explanation of "net torque" in a problem
I hate to ask such a simple question, but I was working on a problem where the idea of "net torque" was calculated differently than I thought. I more or less and just looking for the flaw in my logic and an explanation. :smile:
Here's the main...
Okay, I think I get it, but I wanted to run my reasoning by you real quick to make sure that I'm okay. :) (This will probably be a rehash of what you've been explaining, but it'll probably make me feel better and more sure of myself.)
$\int x' dm = 0$ because if we look at the definition of...
Thanks for your reply, G01. In the frame where the CM is the origin, the CM coordinates are (0, 0). I'm guessing what you mean is that:
2x \int x' dm = 2(0) \int x' dm = 0
2y \int y' dm = 2(0) \int y' dm = 0
If I am on the right track, how do we know that we are treating the center of mass...
Hi, this is my first post here, so please forgive any errors in my post. :)
I'm recently thinking about switching from my major of computer science to physics, and have been brushing up on the first few semesters of physics I had taken a few years ago. I'm currently in the section on...