spherical cordinates

aronclark

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Jul 2, 2014
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Describe the surface above the cone and below the sphere
x^2+y^2=z
x^2+y^2+z^2=z
If a is the angle off the z axis and p is the spherical radius I have
0<=a<=Pi/4 and cosa<=p
My question is what does this describe it appears that it is only the cap of the sphere and is there a better way to write an inequallity to describe p
 
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Describe the surface above the cone and below the sphere
x^2+y^2=z
x^2+y^2+z^2=z^2
If a is the angle off the z axis and p is the spherical radius I have
0<=a<=Pi/4 and cosa<=p
My question is what does this describe it appears that it is only the cap of the sphere and is there a better way to write an inequallity to describe p

Fix that!!
 
Fixed
So my question .is that just the cap of the sphere it appears that it would be to me since the description of p came only fro. the equation of the sphere also is there a better way to write that description in terms of p?
 
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What throws me off that a cone made simply from 0<=t<=Pi/4
Would bit be the same as the cone x^2+y^2=z ir parabolas the inequallity of p will not describe the cone since it was durived from the sphere so for p on the sphere this must not describe any points in the cone yet this us our solution for above the cone under the sphere
 
The only "complication is that the sphere is centered at \(\displaystyle (0, 0, \frac{1}{2})\) rather than (0, 0, 0). In spherical coordinates, the sphere is given by \(\displaystyle x^2= y^2+ z^2= \rho^2= z= \rho cos(\phi)\) or \(\displaystyle \rho= cos(\phi)\). The cone is given by \(\displaystyle x^2+ y^2= \rho^2 sin^2(\phi)= z= \rho cos(\phi)\) or \(\displaystyle \rho= \frac{cos(\phi)}{sin^2(\phi)}\).

The volume of the region above the cone but below the sphere is given by
\(\displaystyle \int_{\theta= 0}^{2\pi}\int_{\phi= 0}^{\pi/4}\int_{\rho= \frac{cos(\phi)}{sin^2(\phi)}}^{cos(\phi)} \rho^2 sin(\phi)d\rho d\phi d\theta\)
 
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