[net.space] more pressure discussion

lew (11/24/82)

Steven Gutfreund posed the question, "Do you really think that if I put
my hand in a vacuum bottle, my blood will start to boil?"

My answer is, "No, the pressure in your hand must stay at your body's
pressure - but your hand will very likely burst."

(I am assuming a seal at the wrist.)

Here we have a contrived example which fulfills the condition so
often erroneously presumed to obtain when a human body is exposed to
a vacuum. The condition being a pressure difference of 16 psi.

I doubt that the suction required to create a "hickey" is more
than 2 psi. Now imagine 8 times that. I think Steven's reference
to a "mere 16 psi" is completely unwarranted. Try blowing on
a tire gauge sometime (in the privacy of your own home, of course.)
I've never been able to register anything at all. I think it usually
takes one or two psi to move the gauge.

Lew Mammel, Jr. ihuxr!lew