# Pressure in fluids -- Question about water flowing out of the bottom of a vessel

• B
Einstein60
Today, I filled a bottle with water and I created a small hole beneath the bottle on the side. I realized that if I open the cock of the bottle, the water flowed out of the hole but if I close it, the water stopped flowing. WHY?

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## Answers and Replies

Homework Helper
As I understand it, you have a bottle with an opening at the top and a valve on the opening.

You have added a small hole at the bottom (small enough so that air does not bubble in through it). You notice that when the top valve is open that the water flows freely out the bottom. But if you close the valve at the top, water no longer flows out.

If you leave the valve open at the top, does anything flow into the bottle through the opening?

If you close the valve, what happens to the air pressure in the bottle above the water if some water, hypothetically, continues to flow out the hole?

vanhees71 and berkeman
Einstein60
As I understand it, you have a bottle with an opening at the top and a valve on the opening.

You have added a small hole at the bottom (small enough so that air does not bubble in through it). You notice that when the top valve is open that the water flows freely out the bottom. But if you close the valve at the top, water no longer flows out.

If you leave the valve open at the top, does anything flow into the bottle through the opening?

If you close the valve, what happens to the air pressure in the bottle above the water if some water, hypothetically, continues to flow out the hole?
Can you please explain further

Homework Helper
Can you please explain further
Can you answer either question?

vanhees71
Einstein60
No

Motore
Mentor
No
You will do better here if you make an effort. We're here to teach, not to spoon feed.

vanhees71 and jbriggs444
Einstein60
You will do better here if you make an effort. We're here to teach not, not to spoon feed.
Okay.