Download PADI Open Water Diver Certification 2024 Questions and Answers (Graded A+) and more Exams Water Resources Planning and Management in PDF only on Docsity! PADI Open Water Diver Certification 2024 Questions and Answers (Graded A+) pressure of air is expressed as - ANSWER-one bar (metric) or one atm (imperial) 10 mtres/ 33 feet exerts the same pressure as - ANSWER-the whole atmoshpere at 0 mtres/feet (sea level) the total pressure is - ANSWER-1 bar/atm at 10 bar/ 33 feet the total pressure is - ANSWER-2 bar/ atm (one air, one water) Can water be compressed? - ANSWER-no, so its volume and density dont change with pressure changes Your air supply lasts ½ as long at - ANSWER-10 metres/33 feet (2 bar/ata) than at the surface (1 bar/ata). If an object weighs the same as the water it displaces, it neither floats nor sinks. This is - ANSWER-neutral buoyancy two pieces of equipment to control your buoyancy: - ANSWER-your weight system and your BCD (Buoyancy Control Device) To actually change your buoyancy during a dive, you use your - ANSWER-BCD Buoyancy control allows you to: - ANSWER--Descend and ascend at a slow, controlled rate. Stop a descent or ascent and maintain your depth with little effort. Float comfortably on the surface. Save energy and avoid harming sensitive aquatic organisms by swimming neutrally buoyant and controlling your movements. Maintain the underwater visibility by helping you not stir up the bottom. Enjoy one of the sensations unique to diving - "weightlessness." four equipment systems in the scuba kit - ANSWER-1. BCD - Buoyancy control device - adjusts buoyancy as you dive 2. regulator -delivers breathing air at surrounding pressure 3. cylinder 4. weight system BCD inflatable bladder - ANSWER-This is a very durable bag that you inflate or deflate to change your buoyancy. BCD - Cylinder band and harness/jacket - ANSWER-The bladder integrates with an adjustable harness that holds the cylinder on your back. The bladder may be entirely behind you, or wrap partially around your waist and/or over your shoulders. With some systems, you can interchange harnesses and bladders to accommodate sizing and preferences. BCD - LPI (low pressure inflator) mechanism - ANSWER-Usually at the end of a large- diameter hose, the LPI inflates the bladder with air from your cylinder, via the regulator, when you press a button. Another button allows you to deflate the bladder, or inflate it orally. Overpressure/quick exhaust valves - ANSWER-To prevent rupturing the bladder due to overfilling, BCDs have one or more overpressure valves that automatically vent if the BCD is too full. Some may have "quick dump" valves that let you manually release air, which is sometimes easier (due to your position in the water) than using the LPI exhaust. Weight system - ANSWER-Many BCDs have special weight pockets that you can release and drop in an emergency. The more weight you need (like when wearing a buoyant dry suit), the more useful these are. (More about weight systems shortly). The LPI mechanism inflates the BCD with - ANSWER-air from my scuba cylinder Your scuba regulator regulates... - ANSWER-the air flow from your cylinder The first stage of regulator - ANSWER-the "hub" of your regulator. It is a simple and reliable device that supplies air to all the other components. It connects to the cylinder valve either by screwing into it, or with a yoke (clamp system). Either way, an o-ring forms the air-tight seal between the first stage and the cylinder valve. The first stage reduces cylinder pressure to an intermediate pressure, which is 7-10 bar/100-150 psi above the surrounding pressure. You breathe from the ( of regulator ) - ANSWER-second stage - It reduces the first stage intermediate pressure to the pressure around you and delivers air only when you inhale - on demand. It has one-way valves that vent your exhalation. The purge button lets you manually release air from your cylinder. Submersible Pressure Gauge (SPG) - ANSWER-indicates the air pressure remaining in the cylinder so you can manage your air supply. The simplest SPG is a hose with a mechanical gauge that reads the pressure in bar (metric) or psi (imperial, pounds per square inch). It may have other instruments attached in a console. Your SPG may also be built into your dive computer (called an air-integrated computer) rather than be a
