Open water review

What is the primary cause of waves?

• Tides

• Winds

• Currents

• Gravitational pull between the Earth and the sun

Longshore currents always move in the same direction as the prevailing offshore currents

• True

• False

Which of the following factors do we take into account when measuring waves?

• Height

• Length

• Oscillation

• 1st and 3rd are correct

Despite its apparent warmth, divers in tropical water still need to consider the need for thermal protection.

• True

• False

Below what water temperature does you body require some form of thermal protection?

• Depends on the diver

• 30°C/86°F

• 20°C/68°F

• 10°C/50°F

As you descend....

• Colors appear to fade

• Reds and oranges are among the first to disappear

• At 30 meters (100 feet), things appear to be blue and gray

• All of the above

Objects under water appear:

• Closer than on land

• Farther away than on land

• Larger than on land

• 1st and 3rd

Because sound travels faster under water...

• It is harder to determine the direction from which the sound is coming

• It is easier to determine the direction from which a sound is coming

• Sounds appear to be coming from closer than they really are

• Sound appear to be coming from farther away than they really are

Sound travels ___________ times faster compared to air

• 4

• 10

• 25

• 800

If you suspect that you or another diver is suffering from decompression sickness

• Drive yourself or the affected diver to the closest recompression chamber

• Activate the Emergency Medial Service (EMS) system

• Contact Divers Alert Network (DAN)

• 2nd and 3rd are correct