View Single Post
  #7   Spotlight this post!  
Unread 30-06-2005, 17:33
Unsung FIRST Hero
Mike Betts Mike Betts is offline
Electrical Engineer
no team
Team Role: Engineer
 
Join Date: Dec 2001
Rookie Year: 1995
Location: Homosassa, FL
Posts: 1,442
Mike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond repute
Re: Pressure physics problems

Quote:
Originally Posted by dlavery
Mike -

Just a clarification. I seem to remember from my scuba (and a few other) classes) that overburden pressure increases of incompressible materials (e.g. pressure increases associated with increasing water depth) is linear. So in the example cited above, would it not be that 1 liter of compressed air at 100 feet will expand to 2 liters at 66 feet, and 3 liters at 33 feet, and 4 liters at the surface?

-dave
Dave,

I stand by my numbers...

1 atmosphere at sea level
2 atmospheres at 33 ft
3 atmospheres at 66 ft
4 atmospheres at 99 ft

PV=nRT and, assuming that nRT is a constant, P and V are complementary (have an inverse relationship). The pressure at 33 ft is 1/2 of the pressure at 99 ft so that the volume in 2X the volume at 99 ft. Likewise, the pressure at sea level is 1/4 of the pressure at 99 ft such that the volume at sea level will be 4X the volume at 99 ft and 2X the volume at 33 ft.

Like I said, the greatest danger is the last 10 feet. The esophagus is a very powerful muscle. Holding your breath in that last segment of an ascent will severely damage the lung tissues...

Regards,

Mike
__________________
Mike Betts

Alumnus, Team 3518, Panthrobots, 2011
Alumnus, Team 177, Bobcat Robotics, 1995 - 2010
LRI, Connecticut Regional, 2007-2010
LRI, WPI Regional, 2009 - 2010
RI, South Florida Regional, 2012 - 2013

As easy as 355/113...
Reply With Quote