Y by Adventure10, Mango247
Let
and
be the origin,
In space given the vessel formed by the revolution of the segment
about
-axis. Denote the hight from
to the surface of water by
When the vessel is filled with water, drain the water out such that the displacement per time is
at the time of
that is to say, if the total volume of the water drained out till the time
is
then
holds. Find the time required for draining out water.











