Quiz - Physics - Minimum Displacement

[TMHeimer]

They are pretty much the same questions I have in my IDC practice exams. The revised DM course did not have that much dive theory questions if I remember right.

Yes, they are also the same questions from the theory of the "old" DM course I took in 2009.
Irrelevant, but though I have not seen the "new" course material, I think it was a good move to put (a lot of?) this stuff in the IDC. I didn't find any real use for most of it when I was assisting with OW courses. The addition of some more practical stuff in the DM course was also good (like a Deep & S&R aspect).

 

[rhwestfall]

So far, this quiz material content was all in the NAUI MSD (still a non-professional ranking)

 

[wetb4igetinthewater]

So far, this quiz material content was all in the NAUI MSD (still a non-professional ranking)

My understanding is that the NAUI MSD is the most extensive course for non-professionals. I do have the manual in my library, but I have only skimmed it. It looks like a great resource that is quite extensive.

 

[tursiops]

Yes, they are also the same questions from the theory of the "old" DM course I took in 2009.
Irrelevant, but though I have not seen the "new" course material, I think it was a good move to put (a lot of?) this stuff in the IDC. I didn't find any real use for most of it when I was assisting with OW courses. The addition of some more practical stuff in the DM course was also good (like a Deep & S&R aspect).

The reason this is relevant to the DM course is because people will ask the DM questions that they might not ask the instructor, for fear of looking silly or stupid. Asking the DM is safer. It is nice if the DM knows the answer.

 

[Joneill]

That was not the question. Read it again.

I did read it:

"To move the block off the bottom, what is the minimum amount of water that must be displaced from a lifting device?"

...and I maintain that 300 l will NOT move it off the bottom - it would only make it neutral - you would need slightly more than 300 l for the block to move off of the bottom!

 

[tursiops]

[
I did read it:

"To move the block off the bottom, what is the minimum amount of water that must be displaced from a lifting device?"

...and I maintain that 300 l will NOT move it off the bottom - it would only make it neutral - you would need slightly more than 300 l for the block to to move off of the bottom!

OK.

 

[TMHeimer]

The reason this is relevant to the DM course is because people will ask the DM questions that they might not ask the instructor, for fear of looking silly or stupid. Asking the DM is safer. It is nice if the DM knows the answer.

Yes I did read about that in the DM manual10 years ago. No student ever asked me about the "advanced" theory-- like Henry's Law, the pressure/volume/temperature stuff--or the history of Boyle's law, Archemides, etc. I was asked some stuff about equipment. A couple asked me about solo diving. I did have some very interesting talks with students that I recall, but nothing that I recall involving the advanced theory/physiology stuff.
Same experience teaching band 19 years. No one seemed to have questions about the transition from the Classical to the Romantic periods, or the history of modern 12 tone music. They were just interested in what we were playing next.

 

[ToneNQ]

Yes I did read about that in the DM manual10 years ago. No student ever asked me about the "advanced" theory--.......................

I always found it depended on the trip. There'd be a keen diver in the AOW course, or Rescue, that were trying to decide if they wanted to sign up as a DM candidate. If you could talk them through some of the theory they were going to learn, demonstrate that the DM is not just a slave lugging and filling tanks and swimming along at the back of the group. If you grasp the theory in your DM training, the IDC and IE tests are a snap and you could focus on the lessons.

 

[Storker]

No student ever asked me about the "advanced" theory-- like Henry's Law, the pressure/volume/temperature stuff--or the history of Boyle's law, Archemides, etc. I was asked some stuff about equipment. A couple asked me about solo diving. I did have some very interesting talks with students that I recall, but nothing that I recall involving the advanced theory/physiology stuff.

No, but I'm pretty certain that knowing the advanced theory/physiology stuff made you more competent to answer the simple questions and know why you should do stuff to keep your students/customers out of trouble.

Like "don't hold your breath". Rote learning the mantra is one thing. Understanding Boyle's law and how it will make your students' lungs blow up if they mess up enables you to know why it's a bad idea to close your glottis on ascent (which in its simplest form can be approximated with "don't hold your breath"). It's the difference between repeating a mantra and giving informed instruction.

 

[Storker]

Case 1:
Instructor/DM: "don't hold your breath"
Almost every student: "OK"
Instructor/DM (under their breath): "let's hope they remember"

Case 2:
Instructor/DM: "don't hold your breath"
The occasional curious (or deliberately annoying) student: "Why?"
Clueless instructor/DM: "Uuuhhh..."

Case 3:
Instructor/DM: "don't hold your breath"
The occasional curious (or deliberately annoying) student: "Why?"
Competent instructor/DM: "Because it'll blow your lungs up"
The occasional curious (or deliberately annoying) student: "Why?"
Competent instructor/DM: "Because <explanation of Boyle's law>"
The occasional curious (or deliberately annoying) student: "But I've heard divers talking about not inhaling or exhaling to stay motionless. Isn't that holding your breath?"
Competent instructor/DM: "<explanation of the difference between closing your glottis and just not using your diaphragm to inhale or exhale>"