RMV math…

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

The term in question is a RATE, neither a volume nor a pressure.

So.. you must specify the units when discussing the term - similar to when we are talking about the speed of an object; you have to state the units, if you want to ensure clarity.
 
The term in question is a RATE, neither a volume nor a pressure.
volume/time or pressure/time

Everyone agrees it is a rate, the debate is whether it is a pressure rate or a volume rate
 
volume/time or pressure/time

Everyone agrees it is a rate, the debate is whether it is a pressure rate or a volume rate
In a recent poll, 65% of respondents used SAC as volume/time and the other 35% used it as pressure/time. Less respondents used the term RMV, however, 97% used it as volume/time.
 
  • Bullseye!
Reactions: L13
You know, after being a regular on SB for a number of years we seem to always have to define SAC. I wish we and the diving industry would change the acronyms to SACP for surface air consumption pressure and SACV for surface air consumption volume. RMV is not intuitive.

volume/time or pressure/time

Everyone agrees it is a rate, the debate is whether it is a pressure rate or a volume rate
I guess...
 
This is off topic, but responding to

wetb4igetinthewater:

Well Galileo was condemned for his theory that the sun revolved around the earth, so..... :cool:

Galileo was not condemned for his promotion of the heliocentric theory of the solar system. Actually, the church liked the results of this theory since it more accurately predicted major Religious holidays. (At the time, Easter was moving more and more towards winter and its tough to celebrate new life when buried in snow).

Galileo was condemned because he falsely claimed that science was "Absolutely True" (Philosophical construct for that which never changes and can never be wrong ... but science is fallible (can be wrong) and changes (evolves with new data and understanding). It is useful only as long as its theories and laws provide useful applications for understanding the world around us).

He also wrote some extremely damning personal attacks on church clergy, especially the Pope.

So, had he just used his theory to predict holidays he would have been left alone (and he was told so by the church) ... it was insistence that he could never be wrong , as well as his extremely hostile views of clergy, that got him into trouble with the then all-powerful church.

Galileo was given house arrest; many others expressing belief in the heliocentric theory were burned at the stake. (At the time, anything contrary to Aristotle or Ptolemy was considered heresy).

So, while professing belief in the heliocentric theory was certainly a component, it was his arrogance, not natural philosophy (what later became science) that was a major component in his troubles. (not wise to bitterly satire an all powerful pope.)

Many moons ago I did a simplistic view of estimating breathing gas consumption at


and calculating gas density:


 
Regardless of acronym volume/time is tank size agnostic. A cubic foot/liter is the same in any cylinder. I don't know why anyone would use pressure/time as an end point metric.
 

Back
Top Bottom