- #1

sberxa

## Homework Statement

Find I(z) (moment of inertia about the z-axis) bounded by the cone z=sqrt(3(X^2 + y^2)) and the sphere with radius a. Density is inversely proportional to the distance from the z-axis.

## Homework Equations

double integration

## The Attempt at a Solution

basicall, I set up my integral, solved it and got a negative number and was hoping somebody could let me know if my original integral is wrong.

it is:

[tex]\int\int\int(B^3)(sin\Phi)^3[/tex] d[tex]B[/tex]d[tex]\Phi[/tex]d[tex]\Theta[/tex]

please ignore the exponent in the above intergral. I can't figure out this website! It's supposed to be on the same level as the rest of the integral to show you the order I am intergrating with respect to. Thanks!

I put the limits of B from 0 to a, of Phi from 0 to (pi/6) and the limits of Theta from 0 to 2(pi). Intergrate first with respect to B then, phi, then theta.

I'm basically trying to use spherical coordinates to solve this integral.

Thanks!

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