What is the force exerted by water in a container?

[DarkWarrior]

Hello everyone, newbie here.. sorry if I posted this in the wrong place.

We just went over fluids today. And I can’t seem to solve a problem that has to do with force due to pressure. The problem is: An open U shaped container is filled with water to the top. What is the force due to the water on side A?

Now pressure = (density)*(gravity)*(height) I believe.
Force is pressure*area. Since side A is a square, that’s simply length squared for area.

So I believe the equation to use in this case is Force = (density)*(gravity)*(height)*(Area).

But for some reason, I keep getting the wrong answer. Here’s a badly drawn picture of the container. Can anyone give me some pointers?

http://img151.imageshack.us/img151/9338/untitled5vd.th.jpg

 

[Doc Al]

Since it's an open container, don't forget to include the effect of atmospheric pressure. Otherwise, your thinking is correct (assuming you use the correct height).

 

[Pyrrhus]

Looks ok to me, Maybe you should check your units.

 

[DarkWarrior]

Thank you for the help! Turns out it was atmospheric pressure. You have to add it to the pressure of the water and then multiply by area to get force.

I should read more carefully. :)