bp/w vs. jacket vs. back-inflate
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diverdown13:All these questions are great, but who wants to give me answers?
Describe a Seche Disk.
What is it used for?
Who made NitrOx popular in the Keys?
Define Benthic.
Is the term FSW a measure of
a) Depth
b) Pressure
c) All of the above
What was the first nationwide SCUBA certification agency in the US?
Who was the first woman to head a major certification agency?
What is the largest shark? the smallest?
Define littoral
and sessile
What's good about it?
diverdown13:well, I actually did want too, but I ended up having a ton of great questions, and no good answers, and then I got all backed up, got a buch of different answers for certain questions and eventually gave up.
thanks for the answers!!!!
miketsp:A diver is in a boat in the middle of a fresh water lake.
He empties the beer cooler which contained 100lbs of ice cubes into the water.
The ice cubes float around for a while and then melt.
What happens to the level of the lake with respect to the shoreline?
a) No change at any moment.
b) Drops then rises.
c) Rises then drops.
Answer (a) Explanation. While the ice cubes are in the boat the boat sinks a little to displace 100lbs of water. When they are thrown into the water they continue to displace 100lbs of water even though they are less dense, and occupy more volume. But the excess volume sticks out above the surface. As they melt they turn into 100lbs of water. So the shoreline never moves, (other than the ripples produced).
And on a similar theme
A diver is in a boat in the middle of a fresh water lake.
He throws a 40lb steel anchor into the water.
What happens to the level of the lake with respect to the shoreline?
a) No change.
b) Drops.
c) Rises.
Answer (b) Explanation. While the anchor is in the boat the boat sinks a little to displace a volume of water whose weight is equivalent to the weight of the anchor. When the anchor goes into the water it only displaces its own volume and since its density is high its own volume is much less than the volume of water that was displaced by the anchor in the boat.
Correct, but once the anchor is in the water, it displaces less than its weight.NetDoc:the weight of the anchor and rope had ALREADY been displaced by the appropriate amount of water while IN the boat.
Find the atmospheric pressure at altitude, and add sufficient oxygen to the breathing gas to reduce the nitrogen fraction proportionally.knotical:At what altitude/Nitrox% combinations do the theoretical depth effects cancel?
knotical:Correct, but once the anchor is in the water, it displaces less than its weight.
Think what happens when you add air to a lift bag to recover the anchor and get it back on the boat.