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I recently started the DMC program at my LDS and we are "diving" into the classroom and test material right away since the season is ending for class checkouts. So now I am getting ready for my first two exams - Physics and Physiology. Might as well get them done first right.
Does anyone have any practice tests or practice questions? I have done the ones in the workbook and am studying the written materials. For me, repetitive practice makes it sink into my thick skull.
Thanks in advance for your help. I am really looking forward to joining the professional part of diving. And ready for the fame and fortune that goes along with it
The tests are not really close to as bad as people make them out to be. Just remember to read the whole question and the whole answers -- like all the rest of the tests you've take up to now.
There's a good thread in this forum info stuck at the top.
I just took the tests. Know the pressure/volume stuff. Know the ear stuff. Read especially the Encyclo. spots that the Workbook mentions. Re the Divemaster Conducted Programs--Read over thoroughly the stuff on the CD Rom. Can't believe I missed 2 questions on an "open book" test--I'd swear the answers weren't anywhere in the CD Rom. But I probably just couldn't find them. Good luck.
Last edited by TMHeimer; November 15th, 2009 at 01:54 AM.
Reason: adding
ok I just took my physics exam, and while I do not feel that the whole section is very relevant to diving and is more about math I did answer a question correctly using math and not knowledge so please help me out.
the question was something like:
a diver uses 46psi/Min at 106 ft how much will he use at 56 ft (same tank but size not given). so I did a math trick and simply cross multiplied and got (46)*(56)=x(106) and then solved and got 24.3psi while this was the correct answer (for this not the test) I assume there was some other method I was supposed to use. I suppose I could have converted psi to F3 then changed depth then recalc psi but I had left it to last and got in a hurry.
SailNaked:
I agree that the math you used does result in the number 24.3 however I do not know if that is actually the correct answer for the problem presented. I am preparing for my physics exam next week and am curious if somebody more familiar with this problem can assist.
I got the following as a solution however I am not saying I am right, hopefully an insturctor can work through this an help us out.
I am assuming we are dealing with sea water, not that it makes a huge difference in this question but I try to be as detailed as possible.
106 ft sea water is 4.21 atmospheres absolute pressure. (106/33+1)
56 feet is 2.69 atmospheres absolute pressure. (56/33+1)
The divers consumption rate of 46psi/min will be 4.21 times less at the surface (Boyles Law regarding gas density). Resulting in a surface consumption rate of 10.9 psi/min (46/4.21).
The diver taking his surface consumption rate of 10.9 to a depth of 2.69 atmospheres (56feet) absolute will use 2.69 times more air at this depth which is 29.32 psi/min. (10.9x2.96)
I am not a physics wiz and I am very much still learning this stuff but this is how I would solve the problem you presented, although I may be a poor lost soul in the world of diving physics as many other DMCs are when getting ready for this part of the program.
I would think your solution is correct as you seem to follow what I would have done if I could have remembered it on the test. however I did not and used simple math, cant say why our answers do not match however I did get the correct answer on the test using about the method I presented (I may have converted the depth as you did to atmospheres first and then cross multiplied).
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Originally Posted by oly5050user
