SDI Exam Study Test Questions and Answers 100% Verified

SDI Exam Study Test Questions and Answers 100% Verified

1. Objects under water appear:: Closer and larger than they do on land
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2. What happens to colors under water: As you descend, colors appear to fade, not intensi
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fy. Blues and grays are the last remaining colors at depth.
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3. Because sound travels faster under water:: Sound's increases speed under water mak
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es it harder to determine the direction from which it is coming.
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4. Water conducts heat away from your body ___________ times faster than air does: 25
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5. The presence of thermoclines means that: divers may require more in the way of exposur
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e protection at depth than they will at the surface.
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6. Tides can:: - make water seem deeper or shallower, stronger and difficult, ad-
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nverse effect on visibility
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7. Cause of permanent ocean currents: The sun warming water near the equator, coupled wi
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th the earth's rotation, is the primary cause of permanent ocean currents.
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8. Wave height and length: Wave height is the distance from its highest point (crest) to its
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lowest point (trough). Wave length is the distance from crest to crest.
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9. formation of surf: A wave encountering shallow water begins to slow at its bottom, while
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nthe top of the wave continues at its previous speed. This causes the wave to break.
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10. what is surge: Surge is the back-and-
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forth movement of water caused by waves passing over head.
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11. What causes most aquatic animal bites?: An animal's defensive response to a perceive
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d threat & mistaken identity
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12. To be injured by an animal with poisonous spines, you must:: Be the aggressor a
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nd touch the animal first.
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13. The states of buoyancy include all of the following except:: Passive
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14. If you feel pain or discomfort during descent:: Ascend to the point where you can comfor
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tably equalize, and only then continue your descent.
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15. Which of the following is the best way to prevent or reduce nitrogen narcosis?:
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16. Any time you cannot inhale while scuba diving (such as when a regulator is out of you
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r mouth), you must be: Exhaling.
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17. What can help prevent decompression sickness (DCS): safety stops, Re-
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, main well within your dive computer's no-
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decompression limit, Ascend no faster than the rate allowed by the dive computer
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18. Contributing factors to decompression sickness can include:: Rapid as-
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cents, 'Pushing" or exceeding your computer's no-
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decompression limits, Heavy exertion and/or dehydration.
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19. best way to prevent or reduce nitrogen narcosis?: Avoid dives below 20 meters/66 f
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eet.




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