I Maximum hole diameter to prevent water leakage

AI Thread Summary
The discussion centers on the challenge of creating a hole in an immersed bottle that prevents water from leaking in at various depths. Key factors include the pressure exerted by the water at different depths and the role of surface tension, which is approximately 72 mN/m at room temperature. To calculate the size of the hole needed to counteract this pressure, one must consider the dimensions of the hole in relation to the water pressure. Participants suggest using the principles of surface tension and pressure calculations to determine the appropriate hole size. Understanding these parameters is crucial for solving the problem effectively.
danex
Messages
1
Reaction score
0
TL;DR Summary
I have a empty bottle and immersed it into the water, where the pressure inside the bottle is equal to air pressure. If I want to make a hole on the bottle, how big is the hole to prevent the water leak into the bottle at different depth?
I have a empty bottle and immersed it into the water, where the pressure inside the bottle is equal to air pressure. If I want to make a hole on the bottle, how big is the hole to prevent the water leak into the bottle at different depth?
what kind of parameter is involve in this phenomena? can some one help me to calculate?
or maybe you can give me a book reference to solve it.
 
Physics news on Phys.org
danex said:
Summary:: I have a empty bottle and immersed it into the water, where the pressure inside the bottle is equal to air pressure. If I want to make a hole on the bottle, how big is the hole to prevent the water leak into the bottle at different depth?

I have a empty bottle and immersed it into the water, where the pressure inside the bottle is equal to air pressure. If I want to make a hole on the bottle, how big is the hole to prevent the water leak into the bottle at different depth?
what kind of parameter is involve in this phenomena? can some one help me to calculate?
or maybe you can give me a book reference to solve it.
What effect are you talking about here?

At a guess, you are talking about surface tension. So you want a hole on the top or bottom of the bottle where the water under pressure corresponding to its depth is restrained by surface tension from dripping into the interior of the bottle.

Google says: "The surface tension of water is about 72 mN/m at room temperature"

Can you put that together with the dimensions of a circular hole to arrive at a figure for pressure?
 
Thread 'Gauss' law seems to imply instantaneous electric field'
Imagine a charged sphere at the origin connected through an open switch to a vertical grounded wire. We wish to find an expression for the horizontal component of the electric field at a distance ##\mathbf{r}## from the sphere as it discharges. By using the Lorenz gauge condition: $$\nabla \cdot \mathbf{A} + \frac{1}{c^2}\frac{\partial \phi}{\partial t}=0\tag{1}$$ we find the following retarded solutions to the Maxwell equations If we assume that...
Maxwell’s equations imply the following wave equation for the electric field $$\nabla^2\mathbf{E}-\frac{1}{c^2}\frac{\partial^2\mathbf{E}}{\partial t^2} = \frac{1}{\varepsilon_0}\nabla\rho+\mu_0\frac{\partial\mathbf J}{\partial t}.\tag{1}$$ I wonder if eqn.##(1)## can be split into the following transverse part $$\nabla^2\mathbf{E}_T-\frac{1}{c^2}\frac{\partial^2\mathbf{E}_T}{\partial t^2} = \mu_0\frac{\partial\mathbf{J}_T}{\partial t}\tag{2}$$ and longitudinal part...
Back
Top