# Pressure in Water Columns...how do they work?

#### Transformers

10+ Year Member
If you have a water column consisting of 4 interconnected columns (A, B, C, D) and the outlet valve is near D...I was curious about how this system actually works...

I.) Lets assume the valve is shut and each column is open to atmospheric air
1.) If the radii are in order (A>B>C>D), then the height of the water in each column would be the same correct because water height should depend on height?
2.) Lets say we now put a lid over the first column, how does that affect the height of the water in the 4 columns?

II.) Lets say we open the valve now
1.) If all columns have the same radii, which flows faster (fluid velocity) and thus decreases in water height more? Intuitively, I would guess column D since it is next to the outlet valve, but I'm not sure how to explain it.
2.) a.) What if the heights of the columns were ordered such that A>B>C>D
and we open the valve? Which column has water decreasing at the
most rapid rate?
b.) What if the heights of the column were ordered such that D>C>B>A
3.) Lastly, how does flow rate apply to the situation (that is Q=Av)?

I realize this was a lot of questions but it all relies on a simple experiemental setup that Im confused about.

Thanks for your help guys...I appreciate anyone who can answer, but I do realize the questions might be a bit long.

OP

10+ Year Member
bmp

OP

10+ Year Member
bmp

OP

10+ Year Member
bump