Convert a barometric pressure of 28" Hg to the corresponding absolute pressure:

To convert barometric pressure measured in inches of mercury (Hg) to absolute pressure in pounds per square inch absolute (PSIA), you need to understand the relationship between these two units. Standard atmospheric pressure at sea level is typically defined as 29.92 inches Hg, which corresponds to 14.7 PSIA.

First, we can find the difference between the standard atmospheric pressure and the given barometric pressure of 28 inches Hg:

1. Calculate the difference from the standard pressure:

29.92 inches Hg - 28 inches Hg = 1.92 inches Hg

2. Convert this difference from inches Hg to PSI. The conversion factor is approximately 0.491 PSI for each inch of mercury:

1.92 inches Hg × 0.491 PSI/inch Hg = 0.94332 PSI

3. To find the absolute pressure, subtract the converted pressure difference from the standard atmospheric pressure in PSI:

14.7 PSIA - 0.94332 PSI = 13.75668 PSIA

Rounding this value gives approximately 13.75 PSIA, making this the correct answer.

Thus, converting from barometric pressure to absolute pressure involves recognizing the relationship between the