NAUI Diver Master Exam (New 2024/ 2025 Update) Questions and Verified Answers| 100% Correct| A Grade QUESTION What is the difference in weight between three cubic feet (85 liters) of fresh water and the same volume of sea water? Answer: 4.8 pounds (2.2 kg) QUESTION A dive team wants to recover (lift) a 380 pound (172 kg)(dry weight) anchor from the bottom of the ocean. The anchor displaces 3 cubic feet (85 liters) of sea water. The bottom composition is flat and firm. How many lift bags, rated for 50 pounds (23 kg) of lift each, will it take to recover (lift) the anchor? Answer: 4 bags QUESTION The pressure exerted by any component gas in a mixture is termed the _____ of that gas. Answer: Partial pressure QUESTION The air (or other breathing mixture) that a diver breathes at depth is delivered to the diver by the regulator at _____. Answer: Ambient pressure QUESTION Which of the following is an example of an injury explained by or attributed to Boyle's Law? Answer: Equalization of air spaces Reverse blocks Lung rupture injuries QUESTION One way that heat loss occurs during diving activity is through _____. Answer: Conduction QUESTION Henry's Law states that the amount of gas that will dissolve into a solution is _____ proportional to the partial pressure of that gas and _____ proportional to the absolute temperature. Answer: directly; inversely QUESTION The absolute pressure at 75 feet (23 meters) of sea water is: Answer: 3.27 ata/48.07 psia/3.3 bar QUESTION A sealed flexible container with 10 liters of air in it is submerged to a depth of 82 feet (25 meters) in the ocean. Providing there is no temperature change in the water between the surface and at 82 feet (25 meters), what is the new volume in the container at 82 feet (25 meters)? Answer: 2.87 QUESTION An air consumption rate of 40 psig (2.76 bar) per minute using a 3,000 psig/80 cubic foot (207 bar/11 liter wet volume) cylinder is equal to? Answer: 1.07 cubic feet per minute (30 liters per minute) QUESTION If a diver has a Surface Air Consumption rate of 30 psig (2.07 bar) per minute with an 80 cubic foot/3000 psig (207 bar/11 liter wet volume) cylinder, the same cylinder will last approximately _____ minutes at a depth of 90 feet (27 meters) of sea water if the diver begins his/her ascent with 1000 psig (69 bar) remaining as a safety measure. Answer: 18 QUESTION If a cylinder contains 80 cubic feet (2265 liters) of air at a pressure of 3000 psig (207 bar), approximately how many cubic feet (liters) of air remains in the cylinder at a pressure of 2200 psig (152 bar) if the cylinder temperature remains constant? Answer: 58.6 cubic feet (1659 liters) QUESTION The partial pressure of oxygen in air at a depth of 132 feet (40 meters) of sea water is _____. Answer: 1.05 ata/15.42 psia/1.06 bar QUESTION A dive team diving in a fresh water lake in the summer is at a depth of 20 feet (6 meters). The water temperature at this depth is 85 degrees Fahrenheit (29 degrees Celsius) and one diver in the team has 244 cubic inches (4 liters) of air in her buoyancy compensator (BC). As the team descends to a depth of 60 feet (18 meters), they pass through a thermocline and the water temperature is now 55 degrees Fahrenheit (12 degrees Celsius). If the diver with 244 cubic inches (4 liters) of air in her BC did not add or remove any air from the compensator, the new volume in her BC after arrival at 60 feet (18 meters) would be how many cubic inches (liters)? Answer: 132 cubic inches/2.16 liters QUESTION As we inhale air, it moves from the nose and the mouth to the _____ into the two _____ and finally to the microscopic _____. Answer: Trachea, bronchi, alveoli QUESTION The stimulus to breath results primarily from _____ in the bloodstream. Answer: Carbon dioxide QUESTION _____ is the biggest breath you can exhale. Answer: Vital capacity QUESTION The risk of carbon dioxide buildup while scuba diving can usually be forestalled by _____. Answer: Avoiding slow or shallow breathing Maintaining a normal breathing pattern Being in shape for the exertion demanded by the dive planned QUESTION Excess breathing resistance can be caused by improperly tuned regulators and small bore snorkels. Answer: True