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vlad4232
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Homework Statement
Hi, I am trying to solve the following problem, and seem to just be going in circles.
A sphere of radius=4 is "dropped" into a paraboloid with equation z=(x^2)+(y^2).
Find the distance "a" from the origin to the center of the sphere at the point where it will
"get stuck" or stop falling further into the paraboloid.
Homework Equations
sphere radius=4
paraboloid z=(x^2)+(y^2)
What I believe is the eq. for the sphere (x^2)+(y^2)+((z-a)^2)=16
I should add that my teacher has solved it and said that the value for a=16.25 and that trying to solve
the problem assuming that the sphere will stop when the cross section of the paraboloid is equal in diameter to
the diameter of the sphere will yield an incorrect answer (a=16)
The Attempt at a Solution
Well I have tried to solve for z and set them equal to each other, but this yields 1 equation with 3 variables. I have been trying to come up with other equations but thus far have only thought of z=a+4 ==> (x^2)+(y^2)=a+4
Which I don't even think is correct.
I also tried to convert to cylindrical coordinates after solving for z and setting the two equations to each other, getting
0=(r^4)-(r^2)-[2(r^2)a]+(a^2)-16
Which might yield something if i knew what to do with it.
Any suggestions would be very helpful. Thank You
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