Chapter 5 - Principles of Water Flashcards
The forward velocity pressure while water is flowing from a discharge opening is considered:
flow pressure.
page 176
For the same discharge, friction loss varies inversely as the ____ power of the diameter of the hose.
5th power
page 179
Atmospheric pressure at sea level is considered to be:
14.7 psi (100 kPa).
page 174
Because a large amount of heat is required to change water to steam, this allows:
more heat to be absorbed from the fire.
See page 169
Water is considered to be virtually _______ and its weight varies at different _________.
incompressible
temperatures
See page 167
At 212°F (100°C), water converted to steam occupies approximately ____ times its original volume.
1,700
page 169
Which of the following refers to a fire hydrant that receives water from two or more directions?
Circulating feed or looped line
page 184
Which principle of pressure is illustrated when two containers hold two different liquids of different depths, but the pressure at the bottom of each container is approximately the same?
The pressure of a liquid in an open vessel is proportional to the density of the liquid.
page 173
The pressure of a liquid in an open vessel is proportional to the _____ of the liquid.
density
page 173
Which means of moving water uses a primary water source located at a higher elevation than the distribution system?
Gravity system
page 183
In order to convert head in feet to head pressure in psi, you must divide the number of feet by:
2.304
page 175
The portion of total available pressure not used to overcome friction loss or gravity while forcing water through pipes, fittings, hoses, adapters
Residual pressure
page 176
A dead-end fire hydrant is a fire hydrant that:
receives water from only one direction.
page 184
The difference between static pressure and normal operating pressure is:
the friction caused by water flowing through the pipes, valves and fittings.
page 176
A gravity system uses two primary water sources, one at a ____________ and one at a ____________.
higher elevation
lower elevation
page 183
An advantage to having separate piping arrangements for a private water supply system is neither of the systems is affected by ___________ to the other
service interruptions
page 189
When water converts to a gas, water vapor, or steam, the water:
only becomes visible as it rises away from the surface of the liquid and begins to condense.
page 167
If a property is served by both the municipal system and a private source consisting of nonpotable water measures must be taken to prevent:
cross contamination.
page 188
Which type of valve is commonly used on private water supply systems and the words open or shut appear in a window as the valve approaches one position or the other?
Post indicator (PIV) valve
page 186
If a gate valve resists turning after fewer than the indicated number of turns required to close the valve, the:
condition should be reported to the responsible agency.
page 187
The first principle of friction loss states that if all other conditions are the same, friction loss varies directly with:
the length of hose or pipe.
page 178
Which term refers to stored potential energy available to force water through pipes, fittings, hose and adapters?
Static pressure
page 175
The first principle of pressure states that fluid pressure is:
perpendicular to any surface on which it acts.
page 172
What term refers to absolute zero pressure?
Perfect vacuum
page 175
The valves within a water distribution system should be inspected and operated _____ by the water supply utility.
yearly
page 186
Water has greater _______________ than other common extinguishing agents.
page 169
heat-absorbing capacity
When engineers estimate the amount of water that a large city needs, the requirements for fire protection will __________________ those for domestic/industrial needs.
far exceed
page 183
In a grid system, large pipes (mains), with relatively widespread spacing, that convey large quantities of water to various points of the system for local distribution to smaller mains are called:
Select one:
primary feeders.
page 184
Which type of valve has a yoke on the outside with threaded stem that controls the gate’s opening or closing and is most commonly used on sprinkler systems?
Outside screw and yoke (OS&Y) valve
page 186
Friction loss in a water system ________ as length of hose or piping increases
increases
page 180
Force per unit area
pressure
page 170
Rates of consumption allow engineers and fire protection personnel to determine:
adequacy of the water distribution system.
page 188
altitude impacts the production of fire streams because atmospheric pressure:
drops as height above sea level increases
page 176
When a nozzle is above the level of the pump, there is:
pressure loss
page 176
The second principle of pressure states that fluid pressure at a point in fluid at rest is:
the same intensity in all directions.
page 172
For water supply, most communities use a combination of the _________ and ______ systems.
direct pumping
gravity systems
page 183
When a large volume of water is needed in an area fire departments should request:
that water utility department increase water pressure
page 182
Which means of moving water uses one or more pumps that take water from a primary source and discharge it through filtration and treatment processes?
Direct pumping system
page 183
The forward velocity pressure while water is flowing from a discharge opening
Flow pressure
page 176
Water is considered to be:
virtually incompressible
page 167
In a grid system, a network of intermediate-sized pipes that reinforce the grid and aid the concentration of required fire flow at any point are called:
secondary feeders
page 185
When water converts to steam within a closed space, the fire:
may be extinguished by smothering.
page 168
Any pressure less than atmospheric pressure
Vacuum
page 175
The smaller the hose, the greater the __________ needed to deliver the same volume.
velocity
page 179
For the same discharge, friction loss varies inversely as the ______ power of diameter of hose.
fifth
page 179
The most common type of valves used on most public water distribution systems
Nonindicating valves
page 186
For fire protection purposes, ordinary fresh water is considered to weigh:
8.3 lb/gal (1 kg/L).
page 167
The fifth principle of pressure states that the pressure of a liquid in an open vessel is proportional to the ___________________
density of the liquid.
page 173
Most commonly, private water supply systems receive their water from a
municipal water supply system.
page 188
The fourth principle of pressure states that the pressure of a liquid in an open vessel is proportional to
its depth
page 173
The fourth principle of friction loss states that for a given velocity, friction loss is approximately
the same, regardless of pressure on the water.
page 179
a circulating feed or looped line is when a fire hydrant receives water from:
two or more directions
page 184
Who should the fire department coordinate with before flushing hydrants in nonemergency situations?
Local water authority
page 188
Radiant heat easily passes through water, rendering water curtains ___________
ineffective.
page 169
The sixth principle of pressure states that the pressure of a liquid at the bottom of a vessel is independent of:
the shape of the vessel
page 174
The piping for fire protection and domestic/industrial services for private water supply systems are almost always:
separate.
page 189
The third principle of pressure states that pressure applied to a confined fluid is transmitted:
equally in all directions.
page 172
Water may be used to smother fires in a combustible liquid when the liquid’s specific gravity is
higher than 1.
page 168
The second principle of friction loss illustrates that friction loss develops much faster than:
change in velocity.
page 178
What is the MAIN concern of fire departments regarding water treatment facilities?
Maintenance failure or other events could disable pumping station(s) or severely hamper the purification process
page 184
