PADI PADI Physics & Physiology of Diving

Question 1

Which gas law explains why a full scuba tank will show a lower pressure reading on a cold day compared to a warm day?

Accepted Answer

Charles's Law

Answer

Charles's Law states that gas volume (or pressure in a rigid container) is directly proportional to temperature, so colder temperatures reduce pressure in a tank.

Question 2

According to Boyle's Law, what happens to the volume of an air space as a diver descends to greater depth?

Accepted Answer

It decreases proportionally as pressure increases

Answer

Boyle's Law states that at constant temperature, the volume of a gas is inversely proportional to the pressure applied, so air spaces compress as depth increases.

Question 3

What is 'nitrogen narcosis' and at what approximate depth does it typically begin to affect recreational divers?

Accepted Answer

An intoxicating effect of nitrogen under pressure, often noticeable around 100 feet (30 m)

Answer

Nitrogen narcosis is an altered state caused by the narcotic effect of nitrogen under pressure, commonly felt around 100 feet and increasing with depth.

Question 4

What physiological condition results from ascending too quickly and allowing dissolved nitrogen to form bubbles in body tissues?

Accepted Answer

Decompression Sickness (DCS)

Answer

Decompression Sickness (DCS) occurs when rapid ascent causes dissolved nitrogen to come out of solution and form bubbles in tissues and the bloodstream.

Question 5

What does Dalton's Law of Partial Pressures state in the context of scuba diving?

Accepted Answer

The total pressure of a gas mixture equals the sum of the partial pressures of each component gas

Answer

Dalton's Law states that each gas in a mixture exerts pressure independently, and the total pressure equals the sum of all partial pressures — critical for understanding oxygen toxicity and nitrox.

(PADI) Certified Professional Association of Diving Instructors Diver Practice Test

(PADI) Certified Professional Association of Diving Instructors Diver Practice Test

PADI PADI Physics & Physiology of Diving