Mike Hord wrote:
>>>> Once you have the velocity of the water as it leaves the hole,
>>>> plain old highschool physics will give you the parabola.  The
>>>> speed of the water would be a function of the pressure and
>>>> probably the diameter at small diameters.
>>>
>>> It seems not. ...
>>
>> What part of it are you saying seems to be incorrect?
>
> Only that hole size is unrelated to the stream path, which is
> counterintuitive.

You should read what I wrote.  I didn't say the water speed (which
eventually affects the path, but speed is the real question here) was
unrelated to hole size.  I believe the hole diameter is largely irrelevant
when large, and the speed is a function of pressure then.  But at small hole
sizes some effects that can be ignored at large hole sizes start to become
significant.  Look at cappillary action as an example.  For small holes
where surface tension is significant over the area of the hole, there will
be a certain minimum pressue just to cause any flow.  You can easily verify
this yourself with a drinking straw.  Put an end into water, then lift it
above the water.  Some water will remain stuck at the end of narrow straws
completely blocking the straw.  This doesn't work on larger diameter straws.
There are also edge effects of viscous friction.  Small diameters have a
larger portion of the area that is subject to these edge effects, making
them important for small diameters but ignorable for large ones.


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