The figure shows a pond full of water having the shape of a truncated cone. The depth of the pond is 30 m. The atmospheric pressure above the pond is `1.0xx10^(5)` Pa. The circular top surface `(radius=R_(2))` and circular bottom surface `(radius = R_(1))` of the pond are both parallel to the ground The magnitude of the force acting on the top surface is the same as the magnitude of the force acting on the bottom surface. Obtain

Answer

`0120`

Explanation

As force equal `P_(A) a_(A) = P_(B) a_(B)`
where `P_(A)` = pressure at top
`a_(A)` = area of top surface
`P_(B)` = pressure at bottom,
`a_(B)` = area of bottom surface
`P_(B)=P_(0)+hrhog=1xx10^(5)+(30)(1000)(10)=4xx10^(5)`
`(1xx10^(5))(piR_(2)^(2))=(4xx10^(5))(piR_(1)^(2))`
`(R_(1)^(2))/R_(2)^(2)=1/4Rightarrow R_(i)=1/2 R_(2)` .....(1)
and`R_(2)-R_(1) = 4/3 h Rightarrow R_(2)-R_(1)=40`