Faster, Slower or just the same?

Beerzo

Beerzo

Masa'warty 3200... Talk To Me!
Joined
Feb 10, 2006
Messages
1,241
Reaction score
0
Points
36
Location
Scotland
If you take an empty bottle and place the open top under a running tap from a distance of 1 inch. Assuming you can move the bottle down from the tap any given distance, althought the water running into the bottle remains constant. Will it take the bottle longer to fill when its further from the tap than what it would it if was an 1 inch from the tap? :readit:
 
Assuming there is a constant stream flow the bottle moved down away from the tap will fill quicker as the velocity of the falling water will increase as it falls - surely?
 
Its a good one, but surley the closer to the tap the less it has to travel?
 
When do you start the clock? When the water passes through the top of the bottle?

I guess it depends on the supply pressure of the water really.
 
I would say you start the clock as soon the bottle is placed under the water.
 
But if there is constant flow the water has already travelled to the point of fill when you place the bottle in the stream so that time has already passed and not added to the fill time!

If you had 1 litre of water only delivered through the tap and you had to fill a 1 litre bottle then both times would be exactly the same assuming there was a small gap between the bottle and tap. If not then flow rate/ vs fall velocity would have to be calculated.
 
Its so annoying i have been trying to test this at the water fountain in my work for weeks now. I only have a distance of 4 inchs to test this though. When i say test i realy mean something to ammuse me while my bottle is filling up. I seem to have developed an OCD for this.

I would think that the closer to the tap it should fill quicker but then if the flow is constant it would not matter if you moved the bottle a mile below the tap the water flowing into it would be the same, would it not?
 
From what I remember from school/uni this will come down to a terminal velocity kind of thing - if the water is falling below terminal velocity out of the tap, it will be the same no matter what, as you need the same volume to fill the bottle and that rate (in ml/sec or whatever) is coming from the tap - it's controlled by the pressure drop across the spigot.

If your water pressure is really high and coming out above terminal velocity so that it is slowed down by friction then as the water were to fall e.g. 100 ft I think it would slow down and be a little slower. This might be nulled by the fact that you have steady state conditions as you are setting the tap running and then putting the bottle under, so it comes back to the rate thing. Water at that pressure would **** everywhere though I think.
 
I'm offshore right now - I'll see if I can line up a fire pump off the helideck and try filling barrels - will give me something to do while I wait for the chopper!
 
But water falling over a certain height becomes a mist quite quickly does it not? But i get what you mean the water will accelerate till it becomes mist then it will slow down again. I think! :wtf:
 
Beerzo said:
But water falling over a certain height becomes a mist quite quickly does it not? But i get what you mean the water will accelerate till it becomes mist then it will slow down again. I think! :wtf:
Click to expand...

I think that's more the nozzle that determines that - you just need a bigger outlet if you want to keep it together before you reach critical flow. Think about a garden hose setting/pressure washer.
 
Geordie Mike said:
I'm offshore right now - I'll see if I can line up a fire pump off the helideck and try filling barrels - will give me something to do while I wait for the chopper!
Click to expand...

ROTFL :laugh:
 
The water exits the tap at a constant flow rate which is measured in volume per hour. So, if you have a 1 litre bottle, and the water is being pumped at 1 litre per hour, it will take you an hour to fill the bottle. There will be no time difference if the water is already flowing when you put the bottle beneath the tap. If you first put the bottle under the tap, and then start the water flow, there will be a time difference relative to the distance covered by the water from the tap. If the bottle is 1 inch from the tap, the water takes x seconds to travel that 1 inch. If the bottle is 10 inches from the tap, the water takes y seconds to travel 10 inches. As 10 inches is bigger than 1 inch, y will be bigger than x. QED.
 
it will take the same time whether it was 1 inch or 1 mile away, the volume of water from an open tap will remain the same, the speed makes no difference, its the volume that determines the fill rate not the speed in which it is presented.

the only problem you would have would be the dispersal of water over distance, the further it falls the more the surrounding air affects it and the more it would disperse.
 
arthurfuxake said:
The water exits the tap at a constant flow rate which is measured in volume per hour. So, if you have a 1 litre bottle, and the water is being pumped at 1 litre per hour, it will take you an hour to fill the bottle. There will be no time difference if the water is already flowing when you put the bottle beneath the tap. If you first put the bottle under the tap, and then start the water flow, there will be a time difference relative to the distance covered by the water from the tap. If the bottle is 1 inch from the tap, the water takes x seconds to travel that 1 inch. If the bottle is 10 inches from the tap, the water takes y seconds to travel 10 inches. As 10 inches is bigger than 1 inch, y will be bigger than x. QED.
Click to expand...

what he said :end_of_discction:
 
MMMMMMMMMMMMMMMMMMMMM
This looks like another "Would the plane take off? " thread !!!!!!!!!!!!!!!

Personaly i think if the bottle was closser it would fill quicker ,thats only IF your time(ing) from bottle is under tap, NOW if your time(ing) from the moment water hits the bottle lip it would be the same!
 
No one mentioned the bottle was on a plane. Do you think that would make a difference?

Mike
 
depends on if its still on the runway or if has taken off but it doesnt make a difference because of the velocity or something
 
how about if the plane was in a steep dive, then the water would float out of the bottle and all over the cabin, or if it was milk it would smell all nasty after a while, or if it was cranberry juice it would stain your clothes, but at least you can swim through cranberries, and you cant swim through pineapples
 
A4Quattro said:
how about if the plane was in a steep dive, then the water would float out of the bottle and all over the cabin, or if it was milk it would smell all nasty after a while, or if it was cranberry juice it would stain your clothes, but at least you can swim through cranberries, and you cant swim through pineapples
Click to expand...

I don't think a pineapple would fit through the bottle neck.
 
Any way im going to look for the airoplane conveyor belt thread for a bit more excitement
 
You must log in or register to reply here.

Similar threads

IDUA3
stressed out or just bored?
Replies
3
Views
648
dappadan786
D
L1 HCS
The Imaginery Thread. Just imagine..
Replies
15
Views
903
L1 HCS
L1 HCS
Rev-head
Just found new security device for the car
Replies
1
Views
717
HmanS3
HmanS3
@udi A3
I just lost the game
Replies
14
Views
1K
Les 51
Les 51
A3simon
Just picked up the Gallardo
Replies
43
Views
2K
A4Andy
A4Andy
Top
Back