Chapter 20, Problem 1RQ

At what depth below the water surface does the pressure increase to 3.0 atm?

A. 33 feet

B. 66 feet

C. 99 feet

D. 132 feet

Summary Introduction

Introduction:

The ambient pressure with which the diver is surrounded includes the atmospheric pressure and the hydrostatic pressure. Environments with high pressure have a considerable effect on the cardiopulmonary system of the body, such as experienced in scuba diving, hyperbaric medicine, and in deep sea diving. There is an increase in the levels of oxygen, while the blood pressure and heart rate are reduced, along with the heart output.

Answer to Problem 1RQ

Correct answer:

At 99 feet below the water surface, the pressure increases to 3 atm.

Explanation of Solution

Explanation for the correct answer:

Option (c) is given as 99 feet. The pressure inside water linearly increases with depth. This is because of the incompressible nature of water. The pressure increases by 1 atm for every 33 feet below the water surface. The total pressure at 66 feet below the water surface is 2 atm, 1atm contributed by water column and 1 atm by atmospheric pressure of the gases present above the water surface. The pressure becomes 3 atm when the depth is 99 feet. Hence, option (b) is a correct answer.

Explanation for the incorrect answers:

Option (a) is given as 33 feet. The pressure at 33 feet is 1 atm, contributed by water and the atmospheric pressure. At 66 feet depth below the water, the pressure becomes 3 atm. So, it is an incorrect answer.

Option (b) is given as 66 feet. The pressure at 66 feet is 2 atm as it increases by 1 atm for every 33 feet. The pressure gets increased to 3 atm when the depth below the water surface is 99 feet. So, it is an incorrect answer.

Option (d) is given as 132 feet. The pressure at 132 feet will be much higher. It will be 4 atm. The pressure increases by 1 atm for every 33 feet; at 132 feet the pressure will be 4 atm. So, it is an incorrect answer.

Hence, options (a), (c), and (d) are incorrect.

Conclusion

Hence, it can be concluded that at 66 feet below the water surface, the pressure would be 3 atm. The pressure increases by 1 atm when the depth below the water surface increases to 33 feet.