Question

A cylinder has a radius 10 cm. To what height should it be
filled with water so that the thrust in its walls is equal to that on its bottom?​

Answer 1

Answer:

Let :

ρ = density of water

h = height of water in cylinder

= > Thrust at the bottom = F

= > F = Pressure × Area

We know :

Pressure = ρ h g

Area = π r²

= > Thrust on walls = Average pressure × Area

= > F' = ( ρ h g / 2 ( 2 π r h )

When F = F' then

= > ( ρ h g × π r² ) = π r ρ h² g  [ h = r ]

Therefore we get answer.