Mark Gase написал(а):
Center of Gravity... 4D-body
Where is the plot? I want an animated XYZ plot with W as time.
I will do it.
But at first we must solve problems of the 3D body with its centers.
Mark Gase написал(а):
Center of Gravity... 4D-body
Where is the plot? I want an animated XYZ plot with W as time.
Mark! Give me please the f(x, y, z, w) function and see
PS
Mark!
Have you read my letter to You?
Mark and all!
Is this correct center of gravity 3D body?
Yes, those are the coordinates of your CG. But why are you working so hard? The simple mean gives you more accurate answers:
Fred Kohlhepp написал(а):
Yes, those are the coordinates of your CG. But why are you working so hard? The simple mean gives you more accurate answers:
Why so hard? We can calculate CG of plate with not constant density - one part is wood, the second - iron!
If you have two materials with different densities you do a weighted average:
Maybe all (or none) of them.
I suppose calculating the population would give the demographic midpoint, so that is ruled out here. Just geographical data.
Do you include mass of mountains (+ ) and valleys (- )?
What about water mass of lakes and rivers?
OK, maybe it's just about the 'surface':
Do you include sloped surface of mountains and valleys?
What about sea level (some parts of land are flooded daily)?
Luc
I have seen two of them - in Ukraine and Lithuania.
It will be good to see on those marks the calculations (in Mathcad)!
Fred Kohlhepp написал(а):
If you have two materials with different densities you do a weighted average:
We must have same density of points! But points can have different weight!
Need to think.
The extension to two materials is straightforward - see 2D example below. The further extension to 3D is also straightforward (as long as you remember to replace R^2 by R^3, and take cube roots instead of square roots, etc.);
Alan
AlanStevens написал(а):
The extension to two materials is straightforward - see 2D example below. The further extension to 3D is also straightforward (as long as you remember to replace R^2 by R^3, and take cube roots instead of square roots, etc.);
Alan
Yes! It is a piece of watermelon with one grain in the center of gravity
This picture will be on my collection of art objects with Math sense.
See please http://twt.mpei.ac.ru/ochkov/TTMI/21/21.01all.png
5 grains of the piece of watermelon! Do yo know more?
One more example
Our method of searching the center of gravity (mass) has a name Pointillism - Wikipedia