SDI Exams 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 increa...

Objects under water appear: 1: The same size as they do on land. 2: Twice as large as they do on land. 3: Closer and larger than they do on land. 4: Smaller and farther away than they do on land. ~~> Closer and larger than they do on land. As you descend: 1: Colors appear to fade. 2: Red...

One possible indicator that a barrel is likely to shoot poorly is pitting near the crown. ~~> TRUE Lands in the throat are which are uneven in their short points are usually caused by: ~~> Cleaning Rod Damage According to Joe Carlos, what must you do with a barrel to know for certain...

What does "SCUBA" stand for in scuba diving? ~~> It stands for self-contained underwater breathing apparatus. List the three most important scuba diving changes that occurred in the 1950s. ~~> The three most important changes were dive tables, personal dive computers (PDC), and enha...

doesn't fall off, it's a good fit. Name at least one visual and one audible rescue signaling device ~~> Your safety sausage, or a whistle/horn. Name two basic fin designs and describe the main features of each. ~~> Open heel fins are used with boots and full foot fins are used barefo...

If you do not set your dive computer's FO2 prior to every dive, it will typically default to 32 percent. ~~> False All of the following are ways to check for the availability of Nitrox at travel destinations, except: ~~> Consult the Old Diver's Almanac

Oxygen Enriched Air is a term some divers use to refer to Nitrox. ~~> True The air we normally breathe consists primarily of: ~~> Nitrogen and Oxygen A mixture of nitrogen and oxygen in which the percentage of oxygen is greater than that found in air is generally called: ~~> Enric...

List three categories of diving. ~~> Recreational, Commercial and Scientific The category of "Recreational Diving" includes both _________and _______. ~~> Sport and Technical The first civilian diver training in the USA was in Los Angeles county. ~~> True List two characteristics...

Three factors that can affect your suit choice are __________, ___________, and ___________. a. depth of dive, length of dive, body type b. depth of dive, length of dive, water temperature c. air temperature, depth of dive, water temperature d. all of the above should be taken into considerati...

Controlled Study ~~> By comparing a treatment (exposed) group and a control (unexposed) group, you have also made this a _________. Natural Experiment ~~> This involves observation of events that have already happened. Critical Thinking ~~> _________: A term we use to describe log...

Define SCUBA ~~> S - self C - contained U - underwater B - breathing A - apparatus List 3 important scuba diving changes that occurred in 1950s ~~> 1) published USN dive tables 2) invented the personal dive computer 3) equipment manufacturers made improvements to the design and w...

What is the absolute pressure (in atmospheres/bars, ATM) at 20 meters(66 feet) ~~> 2 ATM What will be the volume in a ball that is filled with two cubic feet of air at 99 feet when it's taken to the surface? ~~> 8 cubic feet How many more times dense is the air in a balloon at 4 ATM...

Why is the lathe turning process the most involved? ~~> It involves the greatest investment of tooling. The proper temperature suggested for the browning process was 150°: 200°, but the best way to tell if it is hot enough is if the solution readily evaporates. ~~> True T/F: The lath...

Preparation for disassembly is threefold: Preparation of the Firearm, Preparation of Your Workspace and Tools, and which of the following: ~~> Mental Preparation Which hammer is the workhorse of all the different hammers, capable of handling any project, large or small? ~~> Ball-Peen ...