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WorksheetsELECS 21
Total questions: 50
Worksheet time: 25mins
What is(are) the general source(s) of mechanical drift?
unbalance
inertia of Gimbals
bearing friction
all of the choices
What are the three types of nonmetallic insulating materials that can be used in a
high-temperature environments?
FEP
silicone rubber
extruded polytetrafluoroethylene
all of the choices
In what directions will the compass needle point when the compass is placed in the magnetic field surrounding a wire?
the south pole of the compass will point in the direction of the magnetic lines of force
the north pole of the compass will point in the direction of the current
the south pole of the compass will point in the direction of the current
the north pole of the compass will point in the directions of the magnetic lines of force
What are used when power form a conventional servo amplifier is too small to drive large servo motors (either ac or dc)?
power amplifiers
prime movers
magnetic amplifiers
additional servo amplifiers
The amount of precession that results from a given force is determined by what quantity?
elasticity
rigidity
flexibility
viscousity
The IC synchros or Interior Communication synchros are sometimes called as _____.
reverse synchros
forward synchros
flexible synchros
fixed synchros
What factors determine the rigidity of a gyro?
rotor speed
shape
weight
all of the choices
What is the capacity of the battery for a specific rate of discharge?
rating
cycling
discharging
battery life
The motions of a gyroscope can be analyzed in accordance to what basic quantity(ies)?
spin
precession
torque
all of the choices
How are servo systems classified?
according to their functions
according to their sizes
according to their weights
according to their load capacity
Which of the following is (are) the form(s) of servo systems?
electromechanical
hydraulic
pneumatic
all of the choices
What is another name for a servo system?
closed-loop control system
digital control system
analog control system
open-loop control system
The noise signal can cause ________ to the servo system and must be eliminated.
damage
error
malfunctions
roughness
What is combined with the error signal in the proper ratio to obtain the desired servo operation with reduced overshooting and minimum time tag?
correction voltage
swamp voltage
feedback voltage
trigger voltage
What are the major differences of the dc rate generator and the dc generator?
size
load
prime mover
both A and C
What is the Barkhausen criteria for sustained oscillations?
Aβ = 1
Aβ = -1
Aβ = 0
β = 1/Aβ
What is the cathode of a lead-acid cell?
sponge lead
lead peroxide
sulfuric acid and water
hydroxide
What is a Miller integrator?
sweep generator
function generator
low distortion audio generator
RF generator
What system provides instant response to an error signal but results in the load oscillating about the point of synchronization?
overdamped system
critically damped system
underdamped system
all of the choices
What are the ways to prevent polarization?
vent the cell
use a material that will absorb hydrogen
add a material rich in oxygen
all of the choices
What is the simplest form of damping?
overdamping
underdamping
error-rate damping
friction clutch damping
What is the production of hydrogen gas caused by a portion of the charge current breaking down the water in the electrolyte?
charging
gassing
condensing
evaporating
What is the most suitable oscillator circuit for generating 1 MHz?
Colpitt’s oscillator
Hartley oscillator
tuned collector oscillator
Wien bridge oscillator
A circuit has a source voltage of 100 volts and two 50-ohm resistors connected in series. If the reference point for this circuit is placed between the two resistors, what would be the voltage at the reference point?
10 V
40 V
30 V
50 V
What amplifiers are biased so that collector current is zero (cutoff) for a portion of one alternation of the input signal?
class AB
class A
class C
class B
What amplifiers are biased so that the collector current is cut off during one-half of the input signal?
class A
class B
class C
class AB
What serves as the cathode in a common type of dry cell?
carbon electrode
steel cover
zinc container
nickel terminal
Which of the following types of resistors will overcome the disadvantage of a carbon resistor?
rheostat
molded composition
potentiometer
wirewound resistor
To flush a hydrometer, which of the following liquids should be used?
sulfuric acid
salt water
fresh water
a solution of baking soda and water
The space between and around charged bodies in which their influence is felt. This is also called electric field of force or an electrostatic field.
magnetic field
air gap
free space
dielectric field
What switch is one in which the movement of the switch contacts is relatively independent of the actuator movement?
fast-acting switch
knife switch
snap-acting switch
toggle switch
A _____ is an accurate snap-acting switch and the operating point is preset and very accurately known.
fast-acting switch
knife switch
snap-acting switch
microswitch
The power consumed in a conductor in realigning the atoms which setup the magnetic field is known as what type of loss?
hysteresis loss
field loss
magnetic loss
heat loss
A magnetic shield or screen used to protect a delicate instrument should be made of which of the following materials?
plastic
soft iron
copper
aluminum
The communication stations or terminals in local area network are usually linked by cable and are within ____ feet of each other.
1000
500
1500
2000
The number of record stored in a record block.
density
blocking factor
capacity
capability
________ in a dc motor can be accomplished by reversing the field connections or by reversing the armature connections.
series reversal
shunt reversal
armature reaction
motor reversal
What is the distortion of the main field in a motor by the armature field?
armature distortion
armature loss
armature reaction
armature noise
The evaluation of the performance of an equipment compared to your knowledge of how the equipment should operate with the way it is actually performing is known as _____.
maintenance
troubleshooting
test evaluation
diagnosing
What is a data processing system designed to provide a standardized system for the recall and scheduling of test, measurement and diagnostic equipment into calibration facilities?
MEASURE
DIAGNOSTIC
CALIBRATE
TROUBLESHOOTING
What are the three hazards that could create damage to electrical measuring instrument?
mechanical shock
excessive current flow
exposure to magnetic field
all of the choices
The possibility of electrical shock can be reduce by ensuring all motors, generators and other electronic equipments are at _____.
reference potential
ground potential
110 V
220 V
What are the types of power losses in an inductor?
copper loss
eddy-current loss
hysteresis loss
all of the choices
What is the property existing between two coils so positioned that flux from one coil cuts the windings of the other coil?
coupling
induction
mutual inductance
Faraday’s law
When were mnemonic instruction codes and symbolic addresses developed?
in the early 1950’s
1970s
1960s
1980s
If disks are stored horizontally, how many can be stacked?
no more than 20
no more than 10
no more than 30
no more than 40
What is the temperature range within which a disk will operate?
10 to 50 degrees Celsius
20 to 40 degrees Celsius
50 to 100 degrees Celsius
10 to 20 degrees Celsius
The data cell had a storage capacity of how many characters?
over 200 million
over 100 million
over 50 million
over 300 million
Technological advancement is measured by what, in the electronic computer world?
generations
processor speeds
IC integration
softwares
A set of program instructions, a microprogram, permanently stored in read-only memory.
OS
firmware
BIOS
Software
