Thermodynamic Units and Properties Flashcards
An atmospheric pressure of 15.0 psia is equivalent to…
0.0 psig.
A pressure gauge on a condenser reads 27.0 inches Hg vacuum. What is the absolute pressure
corresponding to this vacuum? (Assume a standard atmospheric pressure of 15.0 psia.)
1.5 psia
Assuming a standard atmospheric pressure of 15.0 psia, 5.0 inches Hg vacuum is equivalent to..
12.5 psia.
If a main steam line pressure gauge reads 900 psig, what is the absolute pressure?
915 psia
Which one of the following is equivalent to 5 psia?
20 inches of mercury (Hg) vacuum
Which one of the following is arranged from the lowest pressure to the highest pressure?
8 psia, 20 inches Hg absolute, 2 psig
Which one of the following is arranged from the highest pressure to the lowest pressure?
2 psig, 20 inches Hg absolute, 8 psia
Which one of the following is approximately equivalent to 2 psig?
17 psia
Which one of the following is arranged from the lowest pressure to the highest pressure?
12 psia, 30 inches Hg absolute, 2 psig
Which one of the following is the approximate condenser vacuum when condenser pressure is 16
inches Hg absolute?
14 inches Hg vacuum
Which one of the following is arranged from the highest pressure to the lowest pressure?
2 psig, 18 inches Hg absolute, 8 psia
The tanks are identical and are being maintained at the same constant water level with 17 psia gas
pressure above the water. The tanks are surrounded by standard atmospheric pressure. The
temperature of the water in the tanks and reference legs is 70°F.
Which one of the level detectors is sensing the greatest D/P?
No. 2
A closed water storage tank is pressurized with nitrogen to prevent air inleakage. Tank pressure is
allowed to vary as water level changes. A differential pressure detector is used to measure the tank
level.
To achieve the most accurate level measurement, the low pressure side of the detector should sense
which one of the following?
The pressure of the gas space at the top of the tank.
The tanks are identical and are being maintained at 17 psia and 70 percent water level (calibration
conditions). They are located in a building that is currently at atmospheric pressure.
If the building ventilation system creates a vacuum in the building, which level detectors will provide
the lowest level indications?
1 and 4
The tanks are identical and are being maintained at 2 psig overpressure, the same constant water level,
and a temperature of 60°F. They are surrounded by atmospheric pressure.
If a leak in the top of each tank causes a complete loss of overpressure, which detector(s) will produce
a lower level indication?
No. 2 and 3