SDI Open Water Scuba Diver Exam | Questions with 100% Correct Answers | Verified | Latest Update 2024 Objects under water appear - ✔✔Closer and larger than they do on land How much faster does sound travel in water, compared to air? - ✔✔4 times Water conducts heat away from your body - ✔✔25 times faster than air does As you descend - ✔✔colors fade, reds and oranges fade first, 30 meters seem blue and gray water temp does your body need thermal protection - ✔✔86 degrees What does SCUBA mean - ✔✔self-contained underwater breathing apparatus When water stratifies itself into layers, according to temperature, the boundary between layers is known as a(n): 1: Halocline. 2: Ichtyocline. 3: Thermodyne. 4: Thermocline. - ✔✔Thermocline What is the primary cause of waves? - ✔✔wind Which of the following factors do we take into account when measuring waves? - ✔✔Height, Length Which of the following is incorrect? - ✔✔Waves are not hazardous to divers during shore dives The consequences of becoming cold under water include the following except - ✔✔improved judgment and coordination Because sound travels faster under water: - ✔✔Its harder to determine the direction from which a sound is coming Entering through surf requires special skills. These skills are often included in beginning scuba course taught in areas in which surf entries are common - ✔✔true which of the following are true - ✔✔Surge is the back -and-forth movement of water caused by passing over head Which of the following are true - ✔✔The sun warming water near the equator, coupled with the earth's rotation, is the primary cause of permanent ocean currents despite its apparent warmth, divers in warm waters still need to consider to wear protection - ✔✔true longshore currents always move in the same direction as prevailing offshore currents - ✔✔false a rip current is a narrow flow of swiftly moving water that runs parallel to shore - ✔✔false the trick to dealing with surge is to anticipate its action in order to avoid contact with stationary objects - ✔✔true what is the most effective way to get out of a rip current - ✔✔swim parallel to shore, until out of current the best time to dive is during a slack tide - ✔✔true we pose greater threat to underwater plants and animals - ✔✔true