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dinospamoni
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Homework Statement
A wedge of a sphere of radius 14 cm (similar to one
segment of an orange) is oriented so that the axis is aligned
with the z-axis, one face is in the xz plane, and the other
is inclined at an angle of α = 29o
, as shown. The wedge is
made of metal having a density of 4500 kg/m3
. In the coordinate system shown, compute a) Ixx, b) Iyy, and c) Izz.
The picture is attached
Homework Equations
I know that
I_xx= ∫(y^2+z^2)ρ dV
I_yy= ∫(x^2+z^2)ρ dV
I_zz= ∫(y^2+y^2)ρ dV
The Attempt at a Solution
I'm having trouble thinking of how to replace the dV with something in terms of x y and z
The first thing I did was find the mass, but I'm not sure if it would help at all
I did V=4/3 π r^3
and then multiplied by 29/360 to find the volume of the wedge and the multiplied by the density.
Also, just thought of this now:
r = (x^2 + y^2 + z^2)^1/2
could I differentiate the volume equation to find dV in terms of r and dr (4 pi r^2 dr)
and substitute in the above expression for r and just tack on dx dy and dz? SOrry if that breaks all rules of physics