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denxnis
Nov1-09, 10:35 PM
1. The problem statement, all variables and given/known data
A swimming pool has dimensions 34.0 m 9.0 m and a flat bottom. When the pool is filled to a depth of 2.30 m with fresh water, what is the force caused by the water on the bottom?

I have the answer to this which is 6.90 x 10^6, however I cannot figure out the pressure on the sides or ends.


2. Relevant equations
Pressure on bottom = water density X gravity x area


3. The attempt at a solution
I understand the water depth has to play into this somehow but I cannot figure out how...
I attempted 9.80 x 2 x 9 = 176.4 kN
and
9.80 x 2 x 34 = 666.4 kN

These were incorrect

rl.bhat
Nov1-09, 10:56 PM
Your relevant equation is wrong.
Check it.

denxnis
Nov1-09, 11:16 PM
Apologies,
ρ = density - P = pressure - F = force - b = bottom of pool -
z = area of pool
Pb = ρgz
Fb = PbA

rl.bhat
Nov1-09, 11:40 PM
z is the depth of the water. Now find the pressure at the bottom Pb and then Fb