1 | P a g e | © copyright 2024/2025 | Grade A+
SDI Exam Questions and Answers |
Latest Update 2024/2025
Objects under water appear:
✓ ~~> Closer and larger than they do on land
What happens to colors under water
✓ ~~> As you descend, colors appear to fade, not intensify. Blues and
grays are the last remaining colors at depth.
Because sound travels faster under water:
✓ ~~> Sound's increases speed under water makes it harder to
determine the direction from which it is coming.
Water conducts heat away from your body ___ times faster than air does
✓ ~~> 25
The presence of thermoclines means that
✓ ~~> divers may require more in the way of exposure protection at
depth than they will at the surface.
Tides can:
Master01 | September, 2024/2025 | Latest update
, 2 | P a g e | © copyright 2024/2025 | Grade A+
✓ ~~> - make water seem deeper or shallower, stronger and difficult,
adverse effect on visibility
Cause of permanent ocean currents
✓ ~~> The sun warming water near the equator, coupled with the earth's
rotation, is the primary cause of permanent ocean currents.
Wave height and length
✓ ~~> Wave height is the distance from its highest point (crest) to its
lowest point (trough). Wave length is the distance from crest to crest.
formation of surf
✓ ~~> A wave encountering shallow water begins to slow at its bottom,
while the top of the wave continues at its previous speed. This causes
the wave to break.
what is surge
✓ ~~> Surge is the back-and-forth movement of water caused by waves
passing over head.
What causes most aquatic animal bites?
Master01 | September, 2024/2025 | Latest update
SDI Exam Questions and Answers |
Latest Update 2024/2025
Objects under water appear:
✓ ~~> Closer and larger than they do on land
What happens to colors under water
✓ ~~> As you descend, colors appear to fade, not intensify. Blues and
grays are the last remaining colors at depth.
Because sound travels faster under water:
✓ ~~> Sound's increases speed under water makes it harder to
determine the direction from which it is coming.
Water conducts heat away from your body ___ times faster than air does
✓ ~~> 25
The presence of thermoclines means that
✓ ~~> divers may require more in the way of exposure protection at
depth than they will at the surface.
Tides can:
Master01 | September, 2024/2025 | Latest update
, 2 | P a g e | © copyright 2024/2025 | Grade A+
✓ ~~> - make water seem deeper or shallower, stronger and difficult,
adverse effect on visibility
Cause of permanent ocean currents
✓ ~~> The sun warming water near the equator, coupled with the earth's
rotation, is the primary cause of permanent ocean currents.
Wave height and length
✓ ~~> Wave height is the distance from its highest point (crest) to its
lowest point (trough). Wave length is the distance from crest to crest.
formation of surf
✓ ~~> A wave encountering shallow water begins to slow at its bottom,
while the top of the wave continues at its previous speed. This causes
the wave to break.
what is surge
✓ ~~> Surge is the back-and-forth movement of water caused by waves
passing over head.
What causes most aquatic animal bites?
Master01 | September, 2024/2025 | Latest update
