Thin Plates with Constant Density (Calculus II)

dm41nes
Messages
4
Reaction score
0
Thank you in advance for the help!

Homework Statement



Find the center of mass of a thin plate of constant density (delta) covering the given region.
The region bounded by the parabola y= x - x2 and the line y= -x



Homework Equations



See attachment question 15 p1

The Attempt at a Solution



See attachment question 15 p2
 

Attachments

  • question 15 p1.png
    question 15 p1.png
    15.8 KB · Views: 566
  • question 15 p2.png
    question 15 p2.png
    36.6 KB · Views: 815
Physics news on Phys.org
I like your last solution on attachment 2 except...
Integral from 0 to 2 (x-x^2-x) dx is not Int (2x - x^2) dx
I think you just have an algebra mistake there.
 
Thank you, well it was x-x^2-(-x). So, I added the double negative to the other x. Thats how I was able to get 2x.


Are these forumulas a certified way to find the center of mass?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
Back
Top