- #1
ParoXsitiC
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Homework Statement
Find volume of a sphere with radius R with a hole drilled through the center of radius b. (b<R)
Homework Equations
cos thera = adj / hyp
The Attempt at a Solution
[itex]4\,\int _{0}^{\arccos \left( {\frac {b}{R}} \right) }\!\int _{0}^{\pi
}\!\int _{b}^{R}\!{\rho}^{2}\sin \left( \phi \right) {d\rho}\,{d\phi}
\,{d\theta}
[/itex]
This is what I am getting with spherical coords but I am unsure if theta goes from 0 to arccos(b/R) or if the rho going from b to R takes care of that gap and instead of I should go from 0 to Pi/2 (multipled by 4).
See picture:
Edit:
Upon looking at the picture and how it would spin around with theta, can this even be done spherically? It seems like it would create spherical hole in the sphere and not a cylindrical drill.
With that in mind here are polar:
[itex]\int _{0}^{2\,\pi }\!\int _{b}^{R}\!2\,\int _{0}^{ \sqrt{-{r}^{2}+{R}^
{2}}}\!r{dz}{dr}\,{d\theta}
[/itex]
Again the problem arises, should I go from the green line or from the red line?
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