The equations are ,
,
and
.
Find the volume of the solid generated by revolving the region about the -axis.
The Volume of the solid solid generated by revolving the region about the -axis, for the function
in the interval
is
.
Here and
.
The volume of the solid is .
Apply formula : .
The volume of the solid is .
The center of mass:
\Let and
be continuous functions such that
on
, and consider the planar lamina of uniform density
bounded by the graphs of
and
.
The moments about the -axis and
-axis are
.
.
The center of mass is
and
, where
is the mass of the lamina.
Find the centroid of the region.
\Here ,
and
.
Find .
Substitute,
and
in
.
Substitute in
.
.
Find .
Substitute,
and
in
.
.
Find the center of mass .
The center of mass is
and
, where
is the mass of the lamina.
Substitute,
and
in
.
Apply formula : .
.
Substitute and in
in
.
.
Substitute and
.
The centroid of the solid is .
The volume of the solid is and centroid is
.