Scuba Diving Final Exam

What will the buoyancy of an object be (positive, neutral, or negative) if it displaces an amount of water: a. more than its own weight? b. less than its own weight? c. equal to its own weight? - Answer- a. positive b. negative c. neutral How does the buoyancy of an object differ in fresh water compared to salt water. - Answer- Because salt water weighs more than fresh water, it causes more buoyancy (more upward force) What is the relationship between increasing and decreasing depth and water pressure? - Answer- With increasing depth the water pressure increases. With decreasing depth the water pressure decreases. What are the absolute pressures, air volume, and air density in atmospheres, for: a. 10m/33ft b. 20m/66ft b. 30m/99ft c. 40m/132ft - Answer- a. 2 bar/ata, 1/2, x 2 b. 3 bar/ata, 1/3, x 3 c. 4 bar/ata, 1/4, x4 d. 5 bar/ata, 1/5, x5 What is the relationship between air volume and density, and how do they vary according to this relationship when pressure increases or decreases? - Answer- Air volume and density change proportionately with pressure. As pressure increases, air volume decreases, and air density increases. As pressure decreases, air volume increases, and air density decreases. What is a "squeeze"? - Answer- A pressure imbalance that pushes tissues into an air space. What is "equalization"? - Answer- The process of adding air to an air space. What are the three ways you can equalize air spaces during descent? - Answer- 1. pinch your nose and blow gently against it 2. wiggling your jaw side-to-side and swallowing