PADI Open Water Diver Certification Exam Graded A+
Question : 1) If an object is neutrally buoyant (does not sink
or float) in fresh water, the same object placed into salt water would A sink. B either sink or float. C do nothing. D float.
CORRECT ANSWER : D float. Salt water is heavier than
fresh water because it has dissolved minerals in it. This means it causes more upward force (buoyancy) on an object. An object that is neutrally buoyant in fresh water would float in salt water because there is greater upward force. See Being a Diver I - Buoyancy and Controlling Buoyancy.
Question : 2) I blow up a balloon, tie it off, and take it to the
bottom of the swimming pool. What will happen to the balloon and the air inside it? A The balloon will get bigger and the air inside the balloon will be less dense (molecules move further apart). B The balloon will get smaller and the air inside the balloon will be more dense (molecules move closer together). C The balloon will get bigger and the air inside the balloon will be more dense. D The balloon will get smaller and the air inside the balloon will be less dense.
CORRECT ANSWER : B The balloon will get smaller and
the air inside the balloon will be more dense (molecules move closer together). As water pressure increases, the volume of an air space will decrease. This causes the density of the air inside to increase and air molecules are pushed closer together. The balloon would get smaller and the air density inside would be greater. See Being a Diver I - Water Pressure and Air Volume Effects.
Question : 3) I turn a glass upside down, trap the air in it by
putting it in water, and then I take the glass down to 10 meters. The air space would A become half the size it was at the surface. B not change in size. C become 1/3 the size it was at the surface. D become 2/3 the size it was at the surface.
CORRECT ANSWER : A become half the size it was at the
surface. At 10 meters, the pressure is 2 bar. An air volume taken to this depth from the surface would decrease and become half the size. See Being a Diver I - Water Pressure and Air Volume Effects.
Question : 4) If I am not able to equalize (clear) my body air
spaces, it may be because I have A seasickness. B heart
disease and high blood pressure. C a cold, allergy or another medical problem. D anxiety.
CORRECT ANSWER : C a cold, allergy or another medical
problem. A cold, or any congestion, can block air passages in your ears and sinuses, making equalization difficult or impossible. See Being a Diver I - The Effects of Increasing Pressure on Body Air Spaces.
Question : 5) If my ears or sinuses hurt while I am descending
(going down), it usually means A my air spaces are equalized.B my mask strap is too tight. C I am feeling a squeeze and need to equalize. D my mask is too small.
CORRECT ANSWER : C I am feeling a squeeze and need to
equalize. Pain in your ears or sinuses means that they aren't equalized. Stop your descent and ascend slightly to relieve pressure on your ears. Then attempt to equalize again. If you can't equalize, end the dive. See Being a Diver I - The Effects of Increasing Pressure on Body Air Spaces.
Question : 6) The best place for me to position an alternate air
source is A loose by my side so I can find it fast. B in the triangle area formed by my chin and the lower corners of my
rib cage. C to the base of my cylinder. D to the back of my BCD between my shoulder blades and waist.
CORRECT ANSWER : B in the triangle area formed by my
chin and the lower corners of my rib cage. Your alternate air source attaches with a quick release in the triangle area formed by your chin and the lower corners of your rib cage.Avoid letting your alternate air source dangle unsecured from your kit. See Equipment I - Regulators.
Question : 7) Lung overexpansion injuries can be caused by A
scuba diving without a buddy. B continuing a dive when not properly weighted. C not drinking enough water before scuba diving. D holding my breath while scuba diving.
CORRECT ANSWER : D holding my breath while scuba
diving. Blocking off your lungs by holding your breath and ascending could cause them to overexpand and rupture, which is a serious injury that could result in paralysis and death.Breathing continuously while scuba diving keeps air passages open allowing expanding air to escape. See Being a Diver I - The Effects of Decreasing Pressure on Body Air Spaces.
