05 - IFSTA Chapter 05 Flashcards
How much does a cubic foot of fresh water weigh?
62.4lbs
When converted to steam, water expands by approximately how many times?
1,700
A 1 inch column of water, 1 foot high exerts what pressure?
0.434
What is the first principle of pressure?
Fluid pressure is perpendicular to any surface on which it acts
What is the second principle of pressure?
Fluid pressure at a point in fluid at rest is the same intensity in all directions
What is the third principal of pressure?
Pressure applied to a confined fluid is transmitted equally in all directions
What is the fourth principal of pressure?
The pressure of a liquid in an open vessel is proportional to its depth
What is the fifth principal of pressure?
The pressure of a liquid in an open vesssel is proportional to the density of the liquid
What is the sixth principal of pressure
The pressure of a liquid at the bottom of a vessel is independent of the shape of the vessel
What is atmospheric pressure at sea level?
14.7
How many feet will 1 psi raise a one square inch column of water?
2.304
Above sea level, atmospheric pressure decreases by aproximately how much psi for every 1,000ft?
0.5 psi
The friction loss in older hose can be as much as what percent?
50%
What is the first principle of friction loss?
If all other conditions are the same, friction loss varies directly with the length of the hose or pipe
(Double the length, double the FL)
What is the second principle of friction loss?
When hoses are the same size, friction loss varies approximately with the square of the increase in the velocity of the flow
What is the third principal of friction loss
For the same discharge, friction loss varies inversely as the fifth power of the diameter of the hose
What is the fourth prinicpal of friction loss
For a given velocity, friction loss is approximately the same, regardless of the pressure of the water
What pressure is required to reduce the volume of water by 1 percent?
30,000 psi
What are the most common type of valves used on most public water distribution systems?
Non-indicating
Which of the following cannot affect friction loss in fire hose
Weather
Water is considered to be:
incompressible
Water can be used to smother fires in what kind of combustible liquids?
Those with a specific gravity higher than 1
What principle of water makes it somewhat difficult to soak into dense material?
Its high surface tension
The term force is a simple measure of weight that is expressed in what unit of measurement:
pounds and newtons
Atmospheric pressure that surrounds the earth is:
greatest at low altitudes and lowest at high altitudes
Atmospheric pressure is commonly measured using what substance
mercury
how many times denser is mercury compared to water?
13.55
what is the most common example of gravity fed primary water source?
reservoir
what does a post indicator valve display when the valve stem inside the post is in the “closed” position?
shut
what is the most common type of valve used on a public distribution system?
nonindicating valve
all of the following are basic rates of consumption considered by engineers when desinging a water systems except for:
hourly consumption
which of the following are large pipes with relitevly widespread spacing,that convey large quantities of water to various points in the system?
primary feeders
which of the following best describes the term “elevation” in the fire service?
centerline of the pump to the bottom of the static water source
What is the atmospheric pressure at sea level?
14.7 psi
control valves found in a public water system are typically:
gate valves
which best describes the third princiople of water pressure?
confined fluid is transmitted equally in all directions
What does one cubic foot of water weigh?
62.4lbs
Water is a compound of hydrogen and oxygen formed when:
two hydrogen atoms combine with one oxygen atom
where do most private water supply systems receive their water from?
municipal water supply systems
air pressure that is less than atmospheric pressure is reffered to as:
a vacuum
One cubic foot of fresh water weighs how much?
62.4 lbs.
How can the amount of surface area exposed to water can be increased?
Using a fog pattern
When water converts to steam, it expands how many times its original volume?
1700 times
In which way can pressure NOT be measured?
kNa
The speed at which fluid travels through a pipe or hose is known as:
Velocity
Which way does fluid pressure act on a surface?
Perpendicular
How is the the pressure of a liquid in an open container relative to its depth?
Proportional
The pressure that surrounds the earth and exerts pressure on everything is known as:
Atmospheric pressure
The height of a water supply above the discharge orifice is known as:
Head pressure
Stored potential energy available to force water through pipes, fittings, hose an adapters is known as:
Static pressure
The pressure found in a water distribution system during normal consumption demands is known as:
Normal operating pressure
When the original flow of a stream is tripled, the friction loss is:
Increased nine times
How much pressure does it take to reduce the volume of water one percent?
30,000 PSI
Friction loss in a water system increases as the length of hose or piping what?
Increases
What can help recover pressure as friction loss increases?
A nozzle
Which one of the following will NOT affect friction loss?
Appliances
Which is NOT a method of moving water in a system?
Grid system
A grid system is defined as:
Water supply system that utilizes lateral feeders for improved distribution
What is not one of the three basic rates of consumption considered in the design for a water distribution system?
Minimum daily consumption
Private water supply systems are most commonly found in all of these places except:
Residential communities
One cubic foot of water weighs?
62.4 lb/ft3
At 212 degrees, what is the ratio of water to steam coversion?
1:1,700
What temperature can cause problems such as frozen pumps and hoselines during cold weather operations?
32 degrees
Which term is used to describe the simple measure of weight?
Force
Which principle of pressure is described as the pressure of a liquid in an open vessel is proportional to its depth?
4th principle
Which principle of pressure is described as fluid pressure at a point in fluid at rest is the same intensity in all directions?
2nd principle
Which principle of pressure is described as the pressure of a liquid at the bottom of a vessel is independent of the shape of the vessel?
6th principle
What is the atmospheric pressure at sea level?
14.7 PSI
What is the term used to describe any pressure less than atmospheric pressure?
Vacuum
What is the term used to describe the portion of the total available pressure not used to overcome friction loss or gravity while forcing water through pipes, fittings, hoses or adapters?
Residual pressure
Which principle of friction loss explains that friction loss varies directly with the length of the hose or pipe?
1st principle
Which principle of friction loss explains that when the flow remains constant, the friction loss in a hose will derease when the diameter of the hose is increased?
3rd principle
What is the term used to describe a sudden stoppage of water, moving through a hose or pipe, resulting in an energy surge being transmitted in the opposite direction?
Water hammer
Which method for moving water in a system using one or more pumps that takes water from the primary source and discharges it through the filtration and treatment processes?
Direct pumping system
What are the network of intermediate-sized pipes that reinforce the grid within the various loops of the primary feeder system?
Secondary feeders
What are the 3 components make up a grid system in water distribution?
Primary feeder, secondary feeder and distributors
What is the most common type of valve used on most public water distribution systems?
Nonindicating valve
Per IFSTA, how much does 1 gallon of water weigh?
8.3 lb/gal
What is the term used to describe the height of a water supply above the discharge orifice?
Head pressure
What is the pressure losses or gains due to gravity called?
Elevation pressure
At what temperature is water converted to a gas?
Above 212 F
If water is used to smother a fire, what must the specific gravity of the material on fire be?
Greater than 1.0
How many times does water expand to when converted to steam?
1700 times or more
Pressure is defined as what?
Force per unit area
What is the second principle of pressure?
Fluid pressure at a point in fluid at rest is the same intensity in all directions
What is the fifth principle of pressure?
The pressure of a liquid in an open vessel is proportional to the density of the liquid.
What is considered standard atmospheric pressure?
14.7 psi
How much head pressure is created if the water supply is 100 feet above you?
43.4 psi
What is considered the portion of the total available pressure not used to overcome friction loss or gravity while forcing water through pipes, fittings, hoses or adapters?
Residual pressure
What is the third principle of friction loss?
Friction loss varies inversely as the fifth power of the diameter of the hose
What determines the velocity for a given volume of water?
Diameter of the hose
What is a force created by the rapid deceleration of water causing a violent increase in pressure?
Water hammer
What system uses a water source at a higher elevation that the distribution system?
Gravity
Which part of a grid system contains large pipes (mains) with relatively widespread spacing?
Primary feeders
Which part of a grid system contains a grid arrangement of smaller mains serving individual fire hydrants and blocks of consumers?
Distributors
What type of valve is used to control underground water mains found on the supply main of installed fire protection systems where the operating stem of the valve extends above ground through a post?
Post Indicator Valve
Underground water pipes generally made of cast iron, ductile iron, asbestos cement, steel, plastic or?
Concrete
What is considered the average amount of water used per day based on the total amount of water used in a water distribution system?
Average daily consumption
Where are private water supply systems commonly found?
Large commercial, industrial or institutional properties
Who has control over a private water supply system?
The property owner
How much is ordinary fresh water considered to weigh for fire protection purposes?
8.3 lb./gal
When does water exist in a liquid state exist?
between 32 degrees and 212 degrees
When water is converted to steam at 212 degrees, it occupies approximately?
1,700 times its original volume
Force per unit area is a description of?
pressure
Which of the following is a simple measure of weight?
force
Water has a high surface tension that makes it?
somewhat difficult to soak into dense materials
Atmospheric pressure is?
greatest at low altitudes and least at very high altitudes
Atmospheric pressure at sea level is?
14.7 psi
Any pressure less than atmospheric pressure is referred to as a?
vacuum
Which of the following BEST refers to absolute zero pressure?
perfect vacuum
Which of the following BEST refers to the height of water supply above the discharge orifice?
head pressure
Stored potential energy available to force water through pipes, fittings hose and adapters is?
static pressure
