Would You Really Pop Like a Balloon in a Vacuum?

Chris Wood wrote:

I'm still perplexed at the notion that I myself have
a body surface area of about 2.2 sq. meters. This
means that if I'm suddenly placed in a vacuum, the
total force I "feel" goes from:

(2.2 sq. m) x (100,000 N/sq.m) = 220,000N

-- or from about 50,000 lbs to zero, and I wouldn't
be very immediately and violently affected??

Consider the converse situation, if you were to dive to the bottom of
a ten-metre-deep lake. At a gauge pressure near 100 kPa you'll
experience an equivalent 220-kN 'crushing' force -- but aside from
the blood-gas problems others have discussed in the thread, divers
don't seem to suffer any ill effects from forces of this magnitude.

Another exercise to get an idea of the body's resilience might be to
estimate the pressure on an athlete's feet and joints while running
and jumping. Admittedly it's not quite fair to compare compressive
forces directly to the 'explosive' situation in a vacuum, but my
point is that we can sustain surprisingly large stresses, at least
briefly, without harm.

--
Odysseus

"Odysseus" wrote
Chris Wood wrote:

I'm still perplexed at the notion that I myself have
a body surface area of about 2.2 sq. meters. This
means that if I'm suddenly placed in a vacuum, the
total force I "feel" goes from:

(2.2 sq. m) x (100,000 N/sq.m) = 220,000N

-- or from about 50,000 lbs to zero, and I wouldn't
be very immediately and violently affected??

Consider the converse situation, if you were to dive to the bottom of
a ten-metre-deep lake. At a gauge pressure near 100 kPa you'll
experience an equivalent 220-kN 'crushing' force -- but aside from
the blood-gas problems others have discussed in the thread, divers
don't seem to suffer any ill effects from forces of this magnitude.

Another exercise to get an idea of the body's resilience might be to
estimate the pressure on an athlete's feet and joints while running
and jumping. Admittedly it's not quite fair to compare compressive
forces directly to the 'explosive' situation in a vacuum, but my
point is that we can sustain surprisingly large stresses, at least
briefly, without harm.


45 G apparently during rocket tests, though that's like weighing 4 tons, and we
don't last long with 4 tons on us so it must be close to instantaneous to survive that.

Going from 10 meters deep to surface is easily handled by our bodies, an equivalent
change in pressure as 1 atmosphere to 0. In Event Horizon the astronaut
is caught in a passage way that is decompressing and they get him to exhale
the air from his lungs.

Herc

"|-|erc" wrote in message
...
Going from 10 meters deep to surface is easily handled by our bodies, an
equivalent
change in pressure as 1 atmosphere to 0.
Yes, exactly. The pressure change is the same. However, there is a big
difference between going from 2 bar to 1 bar and going from 1 bar to vacuum.
Consider a volume of gas:
Pressure (bar) Relative gas volume
2 1
1 2
0.5 4
0.1 10
0.001 100
Vacuum Very large!

This table is simply a demonstration of Boyles law but shows that gas volume
changes are not linearly proportional to pressure changes. Given a low
enough pressure the gas will expand to fill *any* volume.

SCUBA divers in high altitude lakes where surface pressure is less than 1
bar have to factor in this extra volume change in their decompression
calculations.

Sally

We have such great air pressure on our body,and taking that pressure
away has to have very bad effects(like death) Blowing your ear drums
out.Pulling all the air out of your lungs. Scuba divers only need a suit
to keep warm in cold water. Astronauts need their space suit to keep
their body heat around them,but also need it to keep air pressure close
to the atmospheric pressure so their diaphragms can work. How did we
all forget about the diaphragm Bert PS Could we say natures vacuum
is a very strong negative force?

Well the holidays are coming up,and when I think of the word"POP" I
think of champagne. I think of the cork first(been used for over
3000 years.) It makes a tight fit because of its cellular structure(air
pockets) that push back very hard when compressed. Then the champagne
bottle is made from very heavy glass. The reason for heavy glass and a
tight fitting cork is the considerable power of the gas trapped in
champagne. Its internal pressure is about 70 pounds per square inch,5
times the downward push of the Earth's atmosphere at sea level.
Well you can tell the kids that are drinking Coca-Cola at the
Thanksgiving table that their drink is charged(CO2) with the pressure of
about 60 pounds per square inch.,twice the pressure in a car tire.
Champagne taste best when you drink it out of a long thin glass. As you
all know I'm a beer drinker and when beer has the proper head that makes
me a happy beer drinker. Happy Thanksgiving to all Bert

Could it be we all came out of the sea? I lived by the ocean all my
life.(but not now) I use to walk along the shore of "Revere beach"Ma. It
had a break water,and I could see the waves creating a foam as the waves
slushed up and over the rocks.(reminded me of Bud foam,) Then there was
that long line of foam that tickeled my feet as I stood close to the
last wave that reached my bare feet. It is very nice going to sleep and
hear the foamy roar of the sea. I read that the universe could be made
from foam bubbles.. Was it a foam bubble that burst(BB) that gave forth
the universe? Do we live insite a bubble we call the Milky Way? Is
there a thin membrane(skin of a bubble) that is the thin gap that
seperates what we know today about the cosmos,and what we want to know?
Can are brain ever "POP" this bubble? Or am I only going to blow the
foam off my beer. Bert

"G=EMC^2 Glazier" wrote in message...
...

Well the holidays are coming up,and when I think of the word"POP" I
think of champagne. I think of the cork first(been used for over
3000 years.) It makes a tight fit because of its cellular structure(air
pockets) that push back very hard when compressed. Then the champagne
bottle is made from very heavy glass. The reason for heavy glass and a
tight fitting cork is the considerable power of the gas trapped in
champagne. Its internal pressure is about 70 pounds per square inch,5
times the downward push of the Earth's atmosphere at sea level.
Well you can tell the kids that are drinking Coca-Cola at the
Thanksgiving table that their drink is charged(CO2) with the pressure of
about 60 pounds per square inch.,twice the pressure in a car tire.
Champagne taste best when you drink it out of a long thin glass. As you
all know I'm a beer drinker and when beer has the proper head that makes
me a happy beer drinker. Happy Thanksgiving to all Bert

Happy holidays, Bert!

and to all the rest of you astronomy lovers, too!

Indelibly yours,
Paine