Oops. I meant move a piston. A basic pump is just a piston going up and down in a cylinder with some valves.
Ok no problem.
Some pumps are more solidly built than others and some can pump out more air per second.
Some can compress more atmosphere away from a chamber to allow expansion of atmosphere in greater amounts.
However, all pumps are only working with a very small pressure difference if they are expelling air into atmospheric pressure and there is no particular strength needed to do that.
No they're not. In your mind they're working with a small pressure difference but the reality is the pressure difference is huge.
You don't appreciate it because you're not under that pressure difference.
a clue is the magdeburg hemispheres.
This will tell you that there is no small pressure difference.
The fact you say a strong pump will break the glass STRONGLY suggests there is something you do not understand.
No. I'm 100% certain that you do not understand evacuation of pressure.
Strong or weak the pumps are only working against the same small pressure difference between one atmosphere and whatever the pump can create.
Take some time out to think about what you're saying.
Providing the glass can comfortably handle the small pressure difference it is not going to break because a low pressure difference of only 15 pounds per square inch is suddenly created.
A very small pressure difference would be fine but this is far from it in terms of what we are dealing with.
The best explanation we have for gas behaviour is the kinetic theory of gases which you will have heard of. The gas particles are in rapid movement unless the temperature is reduced to absolute zero. Gases move from one part of a container to another by diffusion.
Yep, it's called expansion from compression.
So before particles can be removed from the cylinder they have to have travelled to the cylinder via their own random movement and remain there before the valve closes.
There's no random movement. The movement is by force and by attachment of ALL molecules.
There are no free flowing/floating particles with free space in between just landing wherever. Life cannot work like that.
It's very simply high verses low pressures created by friction/vibration under pressures at varying frequencies.
The ordinary vacuum pump has no ability to suck on the air or cause it to change direction or do anything at all. The air does its own thing. The ordinary pump does its thing.
You're correct. Nothing sucks in reality. Nothing pulls in reality. It's all push. It's all resistance.
The pumps job is merely to resist pressure by PUSH and nothing else.
The rest is done by expansion of atmosphere following right behind that pushing pump.
And so if you take a piece of delicate glassware and it is comfortably capable of withstanding a vacuum, which is a small pressure difference between low pressure and one atmosphere, it does not matter what pump you connect it to, none of the pumps have any particular ability to create a force which can damage the glass, because the greatest force they can create is only a small 15 pounds per square inch.
You have a bit to learn, seriously. Allow yourself to learn it and you'll open your eyes and mind to reality.
Re: The magdeberg experiment
1. A tiny pump can create a vacuum which even an elephant cannot work against because we are talking about the
small pressure difference of 15 pounds per square inch
over a large area.
2. If there are no leaks the largest most powerful pump in the world can create no more force than the smallest pump in the world providing both can create the same small pressure difference and sufficient time is allowed for the small pump to reach the lowest pressure.
3. If delicate glassware is rated for a vacuum it cannot be destroyed by connecting it to the largest vacuum pump in the world, unless for example it is abusively suddenly evacuated and instantly refilled and that cycle is repeated continually and the glassware is not rated for that.
>>a clue is the magdeburg hemispheres.
>>This will tell you that there is no small pressure difference.
The pressure difference per square inch is small. The total force is large. The pressure difference is the small difference in pressure per square inch between inside and out. The only thing a vacuum pump experiment needs to consider is the ability of the pump to create a small pressure difference and the time needed to lower the pressure.
If there are no leaks a tiny pump can evacuate a huge chamber like the one NASA has with no problems whatsoever provided it is allowed to run for a sufficient amount of time. The pressure difference between inside and out is small. Designing a building to withstand that is simple if sufficient money is spent on the structure and we can easily go thru a simple design to show how it can be done using very basic materials.
>>There's no random movement. The movement is by force and by attachment of ALL molecules.
>>There are no free flowing/floating particles with free space in between just landing wherever. Life cannot work like that.
>>It's very simply high verses low pressures created by friction/vibration under pressures at varying frequencies.
I prefer to work with what an ordinary person can demonstrate to another person using simple methods like for example my blind bearing example. If you believe you can reject the science of the last 3 hundred years there is not much I can do about it unless suitable experiments can be considered. Firstly, whatever it is you are talking about has to be understood by me and at the moment I have no idea what you are saying there.
Anyway, for the time being I am supposing we can now agree on the following:
all pumps are only working with a very small pressure difference if they are expelling air into atmospheric pressure and there is no particular strength needed to do that.
No they're not. In your mind they're working with a small pressure difference but the reality is the pressure difference is huge.
You don't appreciate it because you're not under that pressure difference.
a clue is the magdeburg hemispheres.
This will tell you that there is no small pressure difference.1. The pressure difference the pump experiences is very small
2. Whatever large forces the container experiences are a different consideration to the small forces the pump experiences
3. The pressure difference in the magdeburg experiment between the inside and outside of the hemisphere is a small one at only one atmosphere, the hemispheres are however sufficiently large that a large amount of force can be created to keep them together, as far as the pump is considered it only experiences a small force to create those large forces.
4. No matter what size the chamber is, the pump will only work at the same rate for all chambers immediately prior to the lowest pressure being reached and also when it is reached. Neither the pump motor revolutions or the air pressure in the tube leading to the pump can by themselves be used to detect chamber size.