Pumps Chapter 1 pp 1-27 Flashcards
From the Pump Manual:
Physical properties of _ are important to the understanding of fire service hydraulics
Water
From the Pump Manual:
Weight of water varies according to _ and _
Temp and mineral content
From the Pump Manual:
Hydraulics is a branch of the physical sciences that deals with what?
The properties of liquids at rest or in motion
From the Pump Manual:
What are two of the specialized areas within the general field of hydraulics?
Hydrostatics and hydrodynamics
From the Pump Manual:
What specialized area of hydraulics involves the motion and actions of liquids?
Hydrodynamics
From the Pump Manual:
What specialized area of hydraulics involves the pressure and equilibrium of liquids?
Hydrostatics
From the Pump Manual:
What interest does the fire service have in hydraulics?
As it relates to the delivery of water in sufficient quantities to extinguish fires
From the Pump Manual:
What helps the fire service achieve desired quantity of flows and ranges of streams?
Set of applied formulas
From the Pump Manual:
What French mathematician and scientist laid the foundation for modern hydraulics?
Blaise Pascal
From the Pump Manual:
What did Pascal discover?
That pressure in a liquid operates equally in all directions and that this pressure acts at right angles to containing surfaces
From the Pump Manual:
<p>
| What year did Pascal make his discovery about pressure in fluids?</p>
<p>
| 1653</p>
From the Pump Manual:
What is the most popular figure used to express the approx weight of one cubic foot of water?
62.5lbs
From the Pump Manual:
True or false water is practically incompressible
TRUE
From the Pump Manual:
_ is defined as a force divided by the area over which it is delivered
Pressure
From the Pump Manual:
_ pressure of water is directly proportional to it’s depth
Downward
From the Pump Manual:
How much pressure does a one foot high column of water exert per square inch?
0.434
From the Pump Manual:
What is the height of water that would produce exactly one pound of pressure per square inch?
2.304 feet
From the Pump Manual:
Downward pressure of water in an open container is in no way affected by the _ of the container
Shape
From the Pump Manual:
In a liquid what determines how much pressure is present?
Density or weight
From the Pump Manual:
How many times heavier than water is mercury?
13.546
From the Pump Manual:
What height of mercury would produce exactly one pound of pressure per square inch?
.17feet or 2.04 inches
From the Pump Manual:
What substance and the pressure developed by it plays another important role in hydraulic theory?
Air
From the Pump Manual:
What is the atmospheric pressure of the earth at sea level?
14.69 but commonly stated as 14.7
From the Pump Manual:
True or false when additional pressure is applied by some external means to a liquid at rest in a confined area the same additional pressure is transmitted equally and undiminished at every other point in the liquid.
TRUE
From the Pump Manual:
When a hoseline is placed in service from one of the outlets of the standpipe system the static pressure in the standpipe system would be reduced due to what?
the friction loss in the supply lines to the siamese, and in the standpipe itself.
From the Pump Manual:
What are hydrostatics?
The pressure and equilibrium of liquids at rest.
From the Pump Manual:
What are empirical methods?
methods based on experience and observation.
From the Pump Manual:
_____ is the ability of the given liquid to resist shearing forces, and varies from substance to substance.
viscosity
From the Pump Manual:
What type of liquid exhibits greater resistance to movement in response to a force?
A liquid possessing high viscosity
From the Pump Manual:
What effect is caused by the molecular friction within the liquid itself and where the liquid comes in contact with the confining surface?
The laminar effect
From the Pump Manual:
What part of the stream has the greater velocities?
The center of the stream
From the Pump Manual:
What occasions cause the changes from streamline to turbulent?
increase of velocity,increase of area between boundaries,roughness of carrier,attractions, degrees of curvature bends, and number of bends
From the Pump Manual:
What are the two classifications of friction loss?
friction loss that occurs due to the motion of a liquid along a smooth or rough surface, and Eddy loss, which occurs at relatively abrubt changes in flow, as at a valve, or direction change, or at sudden enlargement of a channel
From the Pump Manual:
<p>
| What word is used to indicate the quantity of liquid which will pass a given point in a given unit of time?</p>
<p>
| flow</p>
From the Pump Manual:
What is the usual way of expressing volume of flow?
gallons per minute (GPM)
From the Pump Manual:
_____ means the rate of speed at which liquid is moving in relation to same fixed point?
velocity of flow
From the Pump Manual:
If the cross section area in part of an iron pipe were 10 square inches, and the pipe narrowed to a cross section of 2 square inches, and there was a flow of 300 GPM through entire pipe, the velocity of water in the 2 inch area would be ____ of the water in the 10 inch area?
5 times the velocity
From the Pump Manual:
What determines the friction loss?
the velocity of the water
From the Pump Manual:
What types of gauges have been developed to measure the forces involved in hydraulics?
mercury and water manometers, pitot tubes and bourdon gauges
From the Pump Manual:
____ is a device used to measure velocity and pressure heads present within a flowing stream?
pitot tube
From the Pump Manual:
What gauges consist of a curved metal tube, gears and a needle pointer?
bourdon gauges
From the Pump Manual:
What are the 3 kinds of gauges?
those that measure only pressure, those that messure only vacuum and those that measure both.
From the Pump Manual:
On gauges that measure preasure only, what do the calibrations represent?
pounds per square inch
From the Pump Manual:
On gauges that measure vacuum only, what do the calibrations represent?
inches of mercury
From the Pump Manual:
On gauges that measurepressure and vacuum, what do the calibrations represent?
pounds per square inch and inches of mercury
From the Pump Manual:
What can be described as “that pressure present with atmospheric pressure representing zero”?
relative pressure
From the Pump Manual:
____ is described as the actual amount of water pressure present?
absolute pressure
From the Pump Manual:
How much does 1 cubic foot of water weigh?
62.5 pounds
From the Pump Manual:
How many cubic inches are in one cubic foot?
1728 cubic inches
From the Pump Manual:
How many gallons are in one cubic foot of water?
7.481
From the Pump Manual:
How many cubic inches are in one U.S. gallon?
231 cubic inches
From the Pump Manual:
How much does 1 U.S. gallon of water weigh?
8.35 pounds
From the Pump Manual:
How many feet of water exerta pressure of 1 pound per square inch?
2.304 feet
From the Pump Manual:
<p>
| In theory an absolutely perfect positive displacement pump could draft water, how many feet?</p>
<p>
| 33.9 feet</p>
From the Pump Manual:
Are there any fire department pumpingapparatus that can lift water 33.9 feet?
no
From the Pump Manual:
A pump in excellent condition can cause enough vacuum so that atmospheric pressure can force water about ___ feet and one in average condition, about ___ feet?
28 and 26
From the Pump Manual:
One inch of mercury is equivilent to how many pounds per square inch?
.49 pounds per square inch
From the Pump Manual:
What is a static reading?
A reading of an intake gauge on the pumping apparatus at that time(approx 9 inches)would represent a vacuum required solely for lift.
From the Pump Manual:
A reading of the intake gauge, taken when operating with a particular flow of water is what?
A dynamic reading
From the Pump Manual:
If your vacuum is destroyed by air leakage after the pump has been primed, what will happen?
It will cause the pump to lose it’s prime
From the Pump Manual:
What term refers to the pressure prevailing in the hose immediately prior to the waters entrance into the nozzle?
nozzle pressure
From the Pump Manual:
What instrument is a long ended tube with a 90 degree curve at one end?
pitot tube
From the Pump Manual:
Where should the pitot tube be held when testing a stream?
at the center of the stream
From the Pump Manual:
The range of a firefighting stream is dependant upon what 4 factors?
nozzle pressure, nozzle diameter, angle of inclination above horizontal plane and wind speed and direction.
