PADI, Open Water Diver, Final Exam Review
Complete Questions and Guide Answers
100% Verified Graded A+
1. 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.
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.
2. 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.
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 Ettects.
3. 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.
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 Ettects.
4. 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.
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 diflcult or impossible. See Being a Diver
I - The Ettects of Increasing Pressure on Body Air Spaces.
5. 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.
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 Ettects of Increasing Pressure on Body Air Spaces.
6. 6) The best place for me to position an alternate air source is
Complete Questions and Guide Answers
100% Verified Graded A+
1. 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.
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.
2. 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.
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 Ettects.
3. 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.
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 Ettects.
4. 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.
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 diflcult or impossible. See Being a Diver
I - The Ettects of Increasing Pressure on Body Air Spaces.
5. 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.
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 Ettects of Increasing Pressure on Body Air Spaces.
6. 6) The best place for me to position an alternate air source is
