# Physics problem on pressure

1. Jan 1, 2008

### MIA6

1. The problem statement, all variables and given/known data
(a) What are the total force and the absolute pressure on the bottom of a swimming pool 22.0 m by 8.5 m whose uniform depth is 2.0 m? (b) What will be the pressure against the side of the pool near the bottom?

For a), the absolute pressure, I am not sure if I need to add atmospheric pressure? I am little confused with when to include atmospheric pressure. b) To find the pressure against the side of the pool, I need to use total force/Area (height*width)?
Thanks for help.

2. Jan 1, 2008

### mgb_phys

a, is poorly worded - I would guess that absolute pressur eincludes one atmosphereof air pressure as well.
b, The pressure on the side of the pool is the same as the pressure downwards at that point - because water is a fluid.

3. Jan 1, 2008

### MIA6

okay. But can you tell me when do we usually include atmospheric pressure?

4. Jan 2, 2008

### Shooting Star

When the total pressure is comparable to the atm pressure (slightly subjective), or when specifically told in the problem.

5. Jan 19, 2008

### A.M

I think you can add the ATM pressur to gauge pressur If you whant apsolute p .
to calculat total force = apsolute p * Area