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Author Topic: How do I create a vacuum?  (Read 51455 times)

Offline qazibasit

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How do I create a vacuum?
« on: 03/07/2004 23:40:57 »
Can i create a vaccum in a sealed jar with my vaccum cleaner.
« Last Edit: 07/07/2004 01:25:44 by Exodus »


 

Offline Exodus

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Re: How do I create a vacuum?
« Reply #1 on: 04/07/2004 07:51:53 »
quote:
Originally posted by qazibasit

Can i create a vaccum in a sealed jar with my vaccum cleaner.



How are you going to get your vacuum cleaner inside the jar... you must have a very big jar lol! ;)

In terms of creating a vacuum, any container with a valve is suitable for creating a vacuum. Attaching the cleaner to the valve and turning it on will create a vacuum environment within the container, by then closing the valve, a vacuum will remain. Its basic, but it is a vacuum.
 

Offline Quantumcat

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Re: How do I create a vacuum?
« Reply #2 on: 04/07/2004 09:29:27 »
I know a fun way to make a (very partial) vacuum :D

put a glass over your mouth and suck out the air by sucking in into your mouth then into your throat with your mouth shut. You can then go around showing off your glass beak that sticks on all by itself :)

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Offline Exodus

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Re: How do I create a vacuum?
« Reply #3 on: 04/07/2004 09:40:51 »
quote:
Originally posted by Quantumcat

I know a fun way to make a (very partial) vacuum :D

put a glass over your mouth and suck out the air by sucking in into your mouth then into your throat with your mouth shut. You can then go around showing off your glass beak that sticks on all by itself :)

Am I dead? Am I alive? I'm both!




don't do it for too long or you'll get one of those big red rings around your mouth (like the ones people get on their thighs if they spend too long on the toilet reading!). It could be a bit embarrasing!!! ;)
 

Offline neilep

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Re: How do I create a vacuum?
« Reply #4 on: 04/07/2004 13:25:31 »
quote:
Originally posted by Exodus

quote:
Originally posted by Quantumcat

I know a fun way to make a (very partial) vacuum :D

put a glass over your mouth and suck out the air by sucking in into your mouth then into your throat with your mouth shut. You can then go around showing off your glass beak that sticks on all by itself :)

Am I dead? Am I alive? I'm both!




don't do it for too long or you'll get one of those big red rings around your mouth (like the ones people get on their thighs if they spend too long on the toilet reading!). It could be a bit embarrasing!!! ;)



Yep, that's agreat way to form a vacuum....My son did it a while ago Rich and exactly what you said would happen happenned !!!..he had a red mark around his mouth etc for a couple of days....presumably he burst all the little red capilleries or something under his skin eh ?

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Offline qazibasit

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Re: How do I create a vacuum?
« Reply #5 on: 04/07/2004 22:38:47 »
ha ha ha ha so i think this vaccum is a bad thing.
 

Offline chris

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Re: How do I create a vacuum?
« Reply #6 on: 05/07/2004 01:59:46 »
I know someone who took his baby son's rattle (which had a big sucker on the base so it could be attached to a table top or the wall) and stuck it to his forehead, making him look like a Darlek.

When he came to remove the rattle about 10 minutes later he was left with a huge bruise. The negative pressure created by the suction cup had caused blood cells to leak out of his capillaries and into the skin, giving him the appearance of a cyclops !

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Offline neilep

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Re: How do I create a vacuum?
« Reply #7 on: 05/07/2004 02:57:08 »
Would defintely NOT want to try that on any other part of my body !! *smirk*

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Offline gsmollin

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Re: How do I create a vacuum?
« Reply #8 on: 05/07/2004 18:43:56 »
Are you looking for a cheap vacuum pump for an "Amateur Scientist" experiment? Go find a junk refrigerator, and remover the compressor. The inlet end of that makes a great vacuum pump. Now there may be issues with freon these days, unlike when I was doing this, but it's still a good vacuum pump. i used mine to pump out air to make flash lamps for a dye laser experiment.
 

Offline bezoar

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Re: How do I create a vacuum?
« Reply #9 on: 05/07/2004 20:52:33 »
The poor kid with the bruised forehead.  Lucky they didn't call child protection on the dad.
 

Offline qazibasit

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Re: How do I create a vacuum?
« Reply #10 on: 06/07/2004 00:08:35 »
well gsmollin i want to perform the cathode ray tube experiment first performed by jj thomson i want to see the light which comes out of the tube.
 

Offline Exodus

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Re: How do I create a vacuum?
« Reply #11 on: 06/07/2004 02:12:43 »
what experiment is that?
 

Offline Quantumcat

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Re: How do I create a vacuum?
« Reply #12 on: 07/07/2004 17:05:23 »
So that's why your skin goes red when you're hit or whatever? ouch.

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Offline gsmollin

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Re: How do I create a vacuum?
« Reply #13 on: 13/07/2004 19:22:38 »
quote:
Originally posted by qazibasit

well gsmollin i want to perform the cathode ray tube experiment first performed by jj thomson i want to see the light which comes out of the tube.



Are you referring to the q/m ratio experiment? The cathode ray tube has to be highly evacuated. A refrigerator or air conditioner compressor is only a roughing pump, it cannot evacuate a tube highly enough to perform this experiemnt. You will need an oil-diffusion vacuum pump in addition to a roughing pump.
 

Offline qazibasit

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Re: How do I create a vacuum?
« Reply #14 on: 15/07/2004 18:20:43 »
no not the e/m ratio but the one in which the electrons were discovered called the Cathode Ray Experiment the same in which X-rays were discovered too.
 

Offline matrixer

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Re: How do I create a vacuum?
« Reply #15 on: 26/07/2004 20:47:47 »
i ve a good idea to creat vacume in simple way...
all u need is a clean small jar with a airtight cover...just close that cover and take the injection or say sringe and put its needle in the jar's cover and take the air out with the sringe. it will take time but u can create upto 90% vacume in ur jar! u can try it its simple!!!
 

Offline qazibasit

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Re: How do I create a vacuum?
« Reply #16 on: 28/07/2004 11:43:51 »
matrixer i think its impossible the way you are telling it will take you years and you cant create the vaccum.
 

Offline gsmollin

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Re: How do I create a vacuum?
« Reply #17 on: 28/07/2004 14:52:32 »
What your are describing is a piston pump, at least in principle. A refrigerator compressor works in that manner, and will remove much more than 90% of the air. Actually, any good roughing pump will remove about 99.9% of the air. Unfortunately, in order to do the experiment you are contemplating, you must remove 99.9999% of the air.
 

Offline Titanscape

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Re: How do I create a vacuum?
« Reply #18 on: 03/08/2004 07:26:05 »
If you buy a horse syringe and block up one end with no air inside and draw back the plunger then you have a complete vacuum. Use wax or blue tack or tar... Also a little water evapourates at room temperature in that mini environment. You can watch it boil and condense again.

Titanscape
 

Offline gsmollin

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Re: How do I create a vacuum?
« Reply #19 on: 04/08/2004 11:56:40 »
The correct adjective is "partial", not "complete". All these schemes produce partial vacuums, and are useless for any experiments involving electron emission. That requires a "high" vacuum. To achieve high vacuum requires special equipment, at least a roughing pump and an oil diffusion pump.
 

Offline Raghavendra

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How do I create a vacuum?
« Reply #20 on: 21/04/2009 12:22:06 »
You have to take care, that no air should enter in the enironment, or the place where you are going to create vaccum
 

lyner

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How do I create a vacuum?
« Reply #21 on: 21/04/2009 14:11:39 »
I know someone who took his baby son's rattle (which had a big sucker on the base so it could be attached to a table top or the wall) and stuck it to his forehead, making him look like a Darlek.

When he came to remove the rattle about 10 minutes later he was left with a huge bruise. The negative pressure created by the suction cup had caused blood cells to leak out of his capillaries and into the skin, giving him the appearance of a cyclops !
Accident and Emergency Departments have some even more gruesome stories about vacuums and vacuum cleaners!
 

lyner

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How do I create a vacuum?
« Reply #22 on: 21/04/2009 14:17:45 »
You have to take care, that no air should enter in the enironment, or the place where you are going to create vaccum
There is all sorts of stuff on the insides of tubes and containers which will evaporate off and spoil your vacuum.  The 'getter' inside crts and other thermionic valves, which need high vacuum, works by heating  (by induction) a trough of some reactive metal. This reacts with the stray gases in the tube and sticks it to the sides - giving a silvery deposit and removing most of the remaining garbage. There is still some there, though.
 

Offline syhprum

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How do I create a vacuum?
« Reply #23 on: 21/04/2009 16:19:35 »
if you can contrive a 10 meter vertical water filled tube and allow the water level to drop without any air bubbling up a vacuum will form at the top limited by the vapour pressure of the water.
if you use some heavy liquid such as Mercury or tin the drop can be much less but in the case of tin heating is required. 
« Last Edit: 22/04/2009 10:41:41 by syhprum »
 

Offline Bored chemist

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How do I create a vacuum?
« Reply #24 on: 21/04/2009 19:17:07 »
You have to take care, that no air should enter in the enironment, or the place where you are going to create vaccum
This might have been valuable advice back in 2004 when the question was asked but I doubt that th e poster is still waiting for an answer.
 

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How do I create a vacuum?
« Reply #24 on: 21/04/2009 19:17:07 »

 

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