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Cwea Grade 4 Test Part 2 Questions and Answers 100% correct
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Cwea Grade 4 Test Part 2
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Cwea Grade 4 Test Part 2Acid: - answer A substance which releases hydrogen ions
when dissolved in water. Most acids will dissolve
the common metals and will react with a base to
form a neutral salt and water. An acid is the opposite
of an alkali, has a pH rating lower than 7.0,
will turn litmus paper red, and has a sour taste.
Acidity: - answer The quantitative capacity of water or a
water solution to neutralize an alkali or base. It is
usually measured by titration with a standard solution
of sodium hydroxide, and is expressed in
ppm or mg/L of its calcium carbonate equivalent.
Accuracy: - answer The difference between the readings
of an instrument and true value of what is being
measured, expressed as a percent of full
instrument scale.
Air Gap: - answer A clear vertical space through the free
atmosphere, between the lowest opening of any
pipe or faucet conveying water or waste to a tank
plumbing fixture receptor or other device, and the
flood level rim of the receptacle. An air gap is used
to prevent cross connection between a water treatment
device and a possible source of wastewater,
thereby preventing a reverse flow of water from
the sewer into the water supply system. Without
an air gap, such reverse flow could occur due to
an increase in the pressure in the sewer system
or the creation of a negative pressure in the water
supply line. Local plumbing codes usually require
the air gap to be twice the diameter of the inlet,
with a minimum width of 1.5 inches.
Alternating current (AC Power): - answer Electrical current
that alternates direction in cycles called hertz.
American Wire Gage (AWG): The U.S. standard
for wire size.
Alkalinity: - answer The quantitative capacity of water to neutralize an acid; that is, the measure of how
much acid can be added to a liquid without causing
a significant change in pH. Alkalinity is not the
same as pH because water does not have to
be strongly basic (high pH) to have a high alkalinity.
In the water industry, alkalinity is expressed in
mg/L of equivalent calcium carbonate. There are
three kinds of alkalinity: carbonate, bicarbonate,
and hydroxide alkalinity. Total alkalinity is the sum
of all three kinds of alkalinity. Different tests are
used to determine the quantity of the different
kinds of alkalinities present in water.
Automatic Controller: - answer A device that measures the
value of a variable and operates to correct or limit
deviation from a selected reference. It includes
means for both measurement and control.
Automatic Control System: - answer Any combination of
automatic controllers connected in closed loops
with one or more processes.
Automation: - answer The employment of devices, which
automatically control one or more functions in an
industrial process.
Autotransformer: - answer A transformer used to step
voltage up or down. The primary and secondary
windings share common turns, and it provides
no isolation.
Auxiliary Source: - answer A power source dedicated to providing
emergency power to a critical load when
commercial power is interrupted.
BTU: - answer British Thermal Unit. The energy required to
raise one pound of water one degree Fahrenheit.
One pound of water at 32°F requires the transfer
of 144 BTUs change from liquid into solid ice.
Balanced Load: - answer An alternating current power system
consisting of more than two current-carrying
conductors, in which these conductors all carry
the same current.
Backbone: - answer The major multi-channel link in a network, from which smaller links branch.
Battery - answer A collection of cells, grouped together to
provide higher voltage and /or higher current than
a single cell.
Blackout: - answer A total loss of commercial power.
Bonding: - answer Deliberate connection of two or more
points to reduce any difference of potential (voltage).
Branch Circuit: - answer A division of a load circuit, with
current limited by a fuse or circuit breaker.
Break-Before-Make: - answer Operational sequence of a
switch or relay where the existing connection is
opened prior to making the new connection.
Brownout: - answer A low-voltage condition lasting longer
than a few cycles. Brownouts differ from outages
only in duration.
Buck-Boost Transformer: - answer A small, low-voltage
transformer placed in series with the power line
to increase or reduce steady-state voltage.
Busbar: - answer A heavy, rigid conductor used for high
voltage feeders.
CM: Common Mode. - answer The term refers to electrical interference which is measurable as a ground-referenced signal. In true common mode, a signal is common to both the current-carrying conductors.
CPU: - answer Abbreviation for Central Processing Unit,
which is pronounced as separate letters. The
CPU is the brain of the computer. Sometimes
referred to simply as the processor or central
processor, the CPU is the most important element
of the computer system.
Calibration: - answer The procedure laid down for determining,
correcting, or checking the absolute
values corresponding to the graduations on a
measuring instrument.
Capacitance: - answer A measure in units of quantity that is determined by the type of quantity contained
and the type of reference variable.
Capacitor: - answer Two plates or conductors separated by
an insulator. Applying a voltage across the plates
causes current to flow and stores a charge.
Capacitors resist changes in voltage.
Chemical Oxygen Demand (COD): - answer A measure of the oxygen-consuming capacity of organic matter present in water or wastewater. COD is expressed
as the amount of oxygen consumed
from a chemical oxidant in milligrams per liter
during a specific test.
Chlorinator: - answer Chlorinator: A mechanical device specifically designed
to feed chlorine gas or pellets, or a solution
such as hypochlorides, into a water supply in
proportion to the flow of water.
Chlorine: - answer A chemical widely used in the disinfection
of water and as an oxidizing agent for organic
matter, iron, hydrogen sulfide, etc. It is available
as a gas, as a liquid in sodium hypochlorite, or as
a solid in calcium hypochlorite. In water, chlorine
reacts with organics to form trihalomethanes
(THM) which can cause cancer
Chlorine Demand: - answer A measure of the amount of chlorine which will be consumed by organic matter in water before chlorine residual will be found.
Circuit: - answer The complete path of an electric current,
including the source of the current.
Clamp-on CT: - answer A current transformer which
clamps around a current-carrying conductor so
the conductor does not have to be opened for
insertion of the transformer primary. It is particularly
suited for monitoring in situations
where current must be sensed at many points
for relatively short periods.
Closed Loop: - answer A combination of control units in
which the process variable is measured and
compared with the desired value (or set point).
If the measured value differs from the desired
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