# Thread: im having trouble with this one.

1. ## im having trouble with this one.

im having some trouble figuring this one out. i would appreciate any help.thanks

An aquarium 8m long, 3m wide, and 3m deep is full of water. Find the following:
the hydrostatic pressure on the bottom of the aquarium
the hydrostatic force on the bottom of the aquarium
and the hydrostatic force on one end of the aquarium

2. a) The formula for hydrostatic pressure is:

$\displaystyle P = \rho gh$

$\displaystyle \rho = density$

$\displaystyle h = \text{distance below surface}$

We know that:

$\displaystyle \rho_{water} = 1,000 \frac{kg}{m^3}$

$\displaystyle h = 3 m$

$\displaystyle g = 9.8 \frac{m}{s^2}$

Therefore:

$\displaystyle P = 1000*9.8*3$

$\displaystyle P = 29.4 kPa$

b) The formula for Force is:

$\displaystyle F = PA$

The Area of the bottom of the tank is:

$\displaystyle A = length*width = 8 * 3 = 24 m^2$

So:

$\displaystyle F = 29400*24$

$\displaystyle F = 705,600 N$

c) I'll have to do later if no one does it by the time I come back.

3. ## thanks for your help

nice thanks a lot i figured out number 3 which was 29400/2*9=132300