Deck 16: Properties of Water and Air

Question 1

In the English system of measurement, area is measured in inches squared.

Answer 1

True

Question 2

The higher the relative humidity, the more moisture present in the air.

Answer 2

True

Question 3

Water flows down a stack without being affected by the air within the stack.

Answer 3

False

Question 4

In a tall building, the water pressure is the same on all floors as long as the water is not running.

Question 5

Mercury test devices are seldom used today.

Question 6

Oxygen is not a safe substitute for compressed air.

Question 7

Testing plastic piping systems with compressed air is safer than with water.

Question 8

Unlike most substances, water

A) expands when it freezes.
B) contracts when it freezes.
C) changes shape when it freezes.
D) freezes at 34 degrees Fahrenheit.

Question 9

To ensure the integrity of trap seals, the pressure variations in a drainage system should not exceed 1 psi.

Question 10

A U-tube manometer must be open at both ends in order to give an accurate reading.

Question 11

A pneumatic test involves a greater risk of injury than a hydraulic test.

Question 12

The relationship between water depth and pressure may be expressed as 0.433 psi/ft of depth.

Question 13

In the English system of measurement, force is measured in pounds.

Question 14

No matter the shape of the container, the water pressure at any given point in the container is determined only by that point's depth from the free surface.

Question 15

The precise amount of water in a U-tube is critical for accurate measurement.

Question 16

If two states of substance are present at the same time, there is ____ the mixture.

A) a range of possible temperatures for
B) no predictability about the temperature of
C) only one possible temperature of
D) no possibility of two phase forms in

Question 17

Pressure gauges based on the Bourdon tube design are available in a wide variety of pressure ranges, case sizes, materials of construction, and cost.

Question 18

Water exists in all of the following states EXCEPT:

A) solid.
B) gel.
C) liquid.
D) gas.

Question 19

A mercury manometer can measure higher pressures than a water manometer.

Question 20

Air has a single chemical constituent.

Question 21

____ is caused by the rapid pressure rise in a column of water that is suddenly stopped by a quick-acting valve.

A) Vibration
B) Turbulence
C) Water hammer
D) Trap seal loss

Question 22

____ states that the product of the volume and absolute pressure of a gas at one condition and temperature is equal to the product of the volume and absolute pressure at a second condition and the same temperature.

A) Pascal's Law
B) Newton's Law
C) Bourdon's Law
D) Boyle's Law

Question 23

Which pressure gauge would be best for a 5 psi air test?

A) 0-10 psi
B) 0-100 psi
C) 0-30 psi
D) 0-5 psi

Question 24

The force of one foot of water column equals

A) 0.430 psi.
B) 0.433 psi.
C) 0.435 psi.
D) 0.438 psi.

Question 25

In its liquid state, water has the highest ____ of any material.

A) molecular activity rate
B) freezing rate
C) specific heat
D) dew point

Question 26

____ is the study of the movement of air or work done by air pressure.

A) Pneumatics
B) Hydraulics
C) Bourdonics
D) Aeration

Question 27

Higher pressures in a water system are normally measured with a ____.

A) Bourdon tube
B) mercury manometer
C) digital manometer
D) J-tube

Question 28

____ states that in a closed container, pressure exerted by the liquid at any point is distributed evenly throughout the liquid.

A) Boyle's Law
B) Charles' Law
C) Dalton's Law
D) Pascal's Law

Question 29

As the height of a water column increases, the pressure at the bottom ____.

A) increases
B) decreases
C) stays the same
D) doubles

Question 30

Which characteristic of water often contributes to freeze breaks in piping?

A) compressibility
B) incompressibility
C) freezing temperature
D) boiling point

Question 31

Water is considered to be a ____ because it is able to dissolve many substances found in nature.

A) conductor
B) radiator
C) solvent
D) neutral substance

Question 32

Which of the following is NOT a major cause of noise in a plumbing system?

A) vibration
B) turbulence
C) water hammer
D) trap seal loss

Question 33

Which of the following is NOT a remedy for water hammer?

A) Installing butterfly or swing-check valves at fixtures or fixture branches.
B) Limiting water flow rate by sizing the water line to the quick-closing valve to 4 fps or less.
C) Installing shock arrestors or air chambers at fixtures and fixture branches.
D) Installing spring-loaded check valves at pump discharge locations.

Question 34

What is the volume of air in an air chamber 4" in diameter and 12" long at a pressure of 80 psig if the chamber is initially filled with air at atmospheric pressure (14.7 psi)?

A) 11.7 cu. in.
B) 18.3 cu. in.
C) 20.1 cu. in.
D) 23.4 cu. in.

Question 35

The instrument used for measuring pressure in a water system is a

A) voltmeter.
B) thermometer.
C) manometer.
D) pneumometer.

Question 36

The change in volume of water as it changes state from liquid to solid can produce pressures of up to

A) 200,000 psi.
B) 250,000 psi.
C) 275,000 psi.
D) 300,000 psi.