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michonamona
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Please excuse my naivete, but this thought experiment has been running through my mind all week.

Suppose you have three people in room. Suppose the room is sealed such that no air can come in and no air can come out. Suppose there's enough oxygen in the room for us to conduct our experiment( what happens to the three individuals after the experiment is irrelevant). Since the room is completely sealed, if one of the three individual takes a step forward, is it the case that the other two will be compelled against their will to move in order to adjust to the displacement created by the first individual?

If not, why?

Thank you,

M
 
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michonamona said:
Please excuse my naivete, but this thought experiment has been running through my mind all week.

Suppose you have three people in room. Suppose the room is sealed such that no air can come in and no air can come out. Suppose there's enough oxygen in the room for us to conduct our experiment( what happens to the three individuals after the experiment is irrelevant). Since the room is completely sealed, if one of the three individual takes a step forward, is it the case that the other two will be compelled against their will to move in order to adjust to the displacement created by the first individual?

If not, why?

Thank you,

M

Say what?
 
The two people won't be compelled to fill in the gap created by the first. Guess why? Because there is air in there, much more quick and much more eager to do the task.
"Ahh! where does the air come from? Didn't I tell the room is sealed."
opps, i forgot to tell but the air comes from the new place occupied by the person A. He leaves vaccancy somewhere but at the same time kicks out air from new place.

Also ponder, what will happen if one of the person enlarges his stomach (without swallowing air), then there is only kicking out, but no vaccancy!

cheers.
(Rest assured that other people won't be compelled, nope.)
 
thecritic said:
The two people won't be compelled to fill in the gap created by the first. Guess why? Because there is air in there, much more quick and much more eager to do the task.
"Ahh! where does the air come from? Didn't I tell the room is sealed."
opps, i forgot to tell but the air comes from the new place occupied by the person A. He leaves vaccancy somewhere but at the same time kicks out air from new place.

Also ponder, what will happen if one of the person enlarges his stomach (without swallowing air), then there is only kicking out, but no vaccancy!

cheers.
(Rest assured that other people won't be compelled, nope.)

Ah of course...about your second point, my instinct tells me that the other two will feel the pressure created by the enlargement of the stomach of the first person. But they won't move because the force created by the enlargement of the stomach will not over power the force exerted by the leg muscles of the other two people. Any other insights?
 
The amount of force created in the air is so small compared to the limit of human sensation that you wouldn't feel anything.

Also, as the air is a fluid, it will simply move itself as its displaced. Simply flexing and making your stomach bigger would have no net effect on any of the occupants of the room. It would simply compress the air very slightly.