The Physics of Pneumatic Office Chairs and Soap Bottles

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wavingerwin
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How do hydraulics in office chairs work? What's the physics involved in it?
What actually happens when we pull the "trigger"?

Additional question:
What's the physics involved in soap bottles?
(the one which 'spits' soap when the "lid" is pushed)
 
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LoL, cool question :). I guess it's not physics as much of being "mechanics", because physics deals with concepts, mechanics deals with applications.

If you're going to ask a question about physics, it should be explained by equations or something like that. The answer in physics won't be as "when you press the thing it pulls something else that causes the release of ... bla bla bla", this is not physics, again, this is mechanics.

Sorry if I'm disappointing you :)

Good luck :)
 
It's an air filled cylinder and a spring. When you sit on it and pull the trigger, you let the air out and it falls. When you take your weight off it and pull the trigger, the spring pushes it up.
 
Chairs use gases so its technically pneumatic not hydraulic. :-p
 
It's an air filled cylinder and a spring. When you sit on it and pull the trigger, you let the air out and it falls. When you take your weight off it and pull the trigger, the spring pushes it up.

Hmm, of course. How did I not figure this before...

Chairs use gases so its technically pneumatic not hydraulic.
Thanks! i love technical stuff

And with the case of soap bottle,
Does it spits soap because when we push the lid, the bottle is airtight, and the soap will escape from the tube. Due to pressure etc..
And the bottle is somehow not airtight as soon as the lid comes back up. So instead of the soap coming back to the bottom of the bottle to fill the 'emptiness', air does.