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Come Inside... => The Library => Topic started by: Barman on September 21, 2008, 12:05:59 PM

Title: Physics Question
Post by: Barman on September 21, 2008, 12:05:59 PM
This has bothered me for a while... so can any of you knuckleheads brainy bonces out there help me...?

Take a container that can be made air-tight - a 2l pepsi bottle for instance.
Half fill it with cold water, screw on the cap and give it a bloody good shake
Open the top and... nothing happens.  noooo:

Now...

Take the same bottle and half fill with hot water
Give it a bloody good shake (not forgetting to screw the top on tightly first)...
Unscrew the cap and "fizzzzz", pressure has built-up inside the bottle  eeek:

Where does that come from then...?  shrugs:
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 12:18:44 PM
The hot water cools as it is shaken. This causes it to contract creating a slight vacuum in the bottle. As you unscrew the cap the "Fizz" is air rushing to fill that vacuum.  whistle:


NEXT!
Title: Re: Physics Question
Post by: Barman on September 21, 2008, 12:35:55 PM
The hot water cools as it is shaken. This causes it to contract creating a slight vacuum in the bottle. As you unscrew the cap the "Fizz" is air rushing to fill that vacuum.  whistle:


NEXT!
Nope!  noooo:

The pressure is positive...
Title: Re: Physics Question
Post by: TG on September 21, 2008, 01:29:22 PM
Dunno.

Lets talk about breasts.  ;D
Title: Re: Physics Question
Post by: Barman on September 21, 2008, 01:29:54 PM
Dunno.

Lets talk about breasts.  ;D
(  o  Y  o  )  cloud9:
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 01:36:34 PM
The hot water cools as it is shaken. This causes it to contract creating a slight vacuum in the bottle. As you unscrew the cap the "Fizz" is air rushing to fill that vacuum.  whistle:


NEXT!
Nope!  noooo:

The pressure is positive...

Sorry but you know I'm right. That is why all hot water systems have an "Expansion" tank. whistle:
Title: Re: Physics Question
Post by: Nick on September 21, 2008, 01:36:47 PM
Professor Wenchy has her own thread for this stuff  whistle:
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 01:37:49 PM
And where is she when she is needed?  angry041:
Title: Re: Physics Question
Post by: Nick on September 21, 2008, 01:38:15 PM
IKEA
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 01:41:05 PM
Prolly  ::)
Title: Re: Physics Question
Post by: Barman on September 21, 2008, 01:44:50 PM
The hot water cools as it is shaken. This causes it to contract creating a slight vacuum in the bottle. As you unscrew the cap the "Fizz" is air rushing to fill that vacuum.  whistle:


NEXT!
Nope!  noooo:

The pressure is positive...

Sorry but you know I'm right. That is why all hot water systems have an "Expansion" tank. whistle:
Yes... cos it expands when you heat it...

Have you tried the bloody experiment or not???   Banghead

John Noakes didn't have these problems on Blue Peter...  noooo:
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 01:48:17 PM
Did it at school at least 50 years ago. Mind we used a screw top glass bottle 'cos PET bottles hadn't been invented.
Title: Re: Physics Question
Post by: Barman on September 21, 2008, 01:49:14 PM
Did it at school at least 50 years ago. Mind we used a screw top glass bottle 'cos PET bottles hadn't been invented.
Ah... that's why you've forgotten that the pressure increases then...  point:
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 01:58:15 PM
 razz:

I failed Physics anyway
Title: Re: Physics Question
Post by: Barman on September 21, 2008, 02:00:43 PM
razz:

I failed Physics anyway
No wonder then...  noooo:
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 02:07:15 PM
razz:

I failed Physics anyway
No wonder then...  noooo:

It doesn't make me a bad person.
Title: Re: Physics Question
Post by: Barman on September 21, 2008, 02:19:29 PM
razz:

I failed Physics anyway
No wonder then...  noooo:

It doesn't make me a bad person.
Nooooo.... just a bad physicist....  whistle:
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 02:26:51 PM
razz:

I failed Physics anyway
No wonder then...  noooo:

It doesn't make me a bad person.
Nooooo.... just a bad physicist....  whistle:

(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Fwww.kunama.com%2Fpersonal%2Fblog%2F2006%2F09images%2F20060907a-snoopy.gif&hash=cfabbb66513add1b473ca138c9cb7278db1ad4c4)
Title: Re: Physics Question
Post by: Barman on September 21, 2008, 02:44:48 PM
razz:

I failed Physics anyway
No wonder then...  noooo:

It doesn't make me a bad person.
Nooooo.... just a bad physicist....  whistle:

(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Fwww.kunama.com%2Fpersonal%2Fblog%2F2006%2F09images%2F20060907a-snoopy.gif&hash=cfabbb66513add1b473ca138c9cb7278db1ad4c4)
Welcome to my world...  noooo:
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 02:53:47 PM
(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Fwww.salas.com%2Fweblogs%2Fimages%2FSnoopy.jpg&hash=dad25108ff242b44190bf720abb998fd17dd3f56)
Title: Re: Physics Question
Post by: Barman on September 21, 2008, 03:38:43 PM
(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Fwww.salas.com%2Fweblogs%2Fimages%2FSnoopy.jpg&hash=dad25108ff242b44190bf720abb998fd17dd3f56)
shrugs:
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 03:54:45 PM
(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Fwordylefty.files.wordpress.com%2F2008%2F03%2Flucy-doctor-stand.jpg&hash=68df007d7e0fcddb34ef0091b2ffca39cc8a67ca)

Peanuts has the answer to everything
Title: Re: Physics Question
Post by: Darwins Selection on September 21, 2008, 04:28:05 PM
The hot water cools as it is shaken. This causes it to contract creating a slight vacuum in the bottle. As you unscrew the cap the "Fizz" is air rushing to fill that vacuum.  whistle:


NEXT!

I'm with Snoopy, it sucks.

Unless in your case, it is all the Methane given off by the part-treated sewage in Cyprus water.
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 04:38:39 PM
Ye cannae change the laws of physics Captain.

(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Flightwater.files.wordpress.com%2F2007%2F07%2Fstar-treks-scotty.jpg&hash=370dd2d3bbb3f6fe454b8c31d875823863f8dc3a)
Title: Re: Physics Question
Post by: Barman on September 21, 2008, 04:45:07 PM
The hot water cools as it is shaken. This causes it to contract creating a slight vacuum in the bottle. As you unscrew the cap the "Fizz" is air rushing to fill that vacuum.  whistle:


NEXT!

I'm with Snoopy, it sucks.

Unless in your case, it is all the Methane given off by the part-treated sewage in Cyprus water.
It definitely blows!  Banghead
Title: Re: Physics Question
Post by: Barman on September 21, 2008, 04:46:45 PM
(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Fwordylefty.files.wordpress.com%2F2008%2F03%2Flucy-doctor-stand.jpg&hash=68df007d7e0fcddb34ef0091b2ffca39cc8a67ca)

Peanuts has the answer to everything
What can I get for (https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Fwww.freesmileys.org%2Fsmileys%2Fforum%2F2c.gif&hash=12460a2428827f0f0cf9f48655bc6987a019b1df) (http://www.freesmileys.org)  rubschin:
Title: Re: Physics Question
Post by: Snoopy on September 21, 2008, 04:49:00 PM
The hot water cools as it is shaken. This causes it to contract creating a slight vacuum in the bottle. As you unscrew the cap the "Fizz" is air rushing to fill that vacuum.  whistle:


NEXT!

I'm with Snoopy, it sucks.

Unless in your case, it is all the Methane given off by the part-treated sewage in Cyprus water.
It definitely blows!  Banghead

Calm down dear ~ it's only an internet forum  happy100
Title: Re: Physics Question
Post by: Nick on September 21, 2008, 06:47:05 PM
Line from Maggie Thatcher, sitting on a field gun in the Falklands: "Will this thing blow me off?" (courtesy: Radio 4)