Basic Concepts in Electro Technology
Exam Questions And Answers
/.A typical extra low voltage device would be a:
Select one:
a. toaster
b. set of tree lights
c. door bell
d. residential lighting
/.As back EMF decreases the net armature EMF:
Select one:
a. remains constant
b. decreases
c. increases
d. decreases amount of armature current
/.Prior to using a voltage meter, what must be known:
Select one:
a. type of current
b. type of meter
c. expected measured value
d. if circuit is open or not
/.A property of a magnet, is that it will always point in the north direction:
Select one:
a. freely suspended in the air
b. charged with electricity
c. it is demagnetized
d. in the presence of iron filings
/.An ampere is the _________ of current flow:
Select one:
a. cause
b. resistance
c. measurement
d. reluctance
/.Current transformers step down the current rather than the:
,Select one:
a. resistance
b. voltage
c. conductance
d. number of poles
/.Three phase systems often use__________ to replace three-phase transformers:
Select one:
a. capacitors
b. pancake windings
c. Sandwich windings
d. banks of single-phase
/.Test meters come in 2 basic types, digital and:
Select one:
a. pneumatic
b. DMM
c. analogue
/.A moving conductor is at an angle of 90 degrees within the magnetic field:
Select one:
a. maximum resistance to current flow is attained
b. current will flow with the least resistance
c. motor action will be experienced
d. voltage generated will be at its maximum
/.The flow of electrons in a uniform direction from atom to atom through a circuit is
known as:
Select one:
a. electromotive force
b. potential difference
c. a short circuit
d. current
/.The magnetic field in a DC machine may be supplied by permanent magnets in small
units. Large DC machines use field poles that are essentially:
Select one:
a. insulators
b. resistors
c. non-magnetic
d. electromagnets
/.Three resistors of 170 ohms, 9 ohms, and 570 ohms are connected in series.
Determine the total equivalent resistance:
Select one:
a. 391 ohms
, b. 749 ohms
c. 7490 ohms
d. 3910 ohms
/.The property which determines whether or not a material will be easily magnetized is
called:
Select one:
a. reaction
b. conductivity
c. permeability
d. magnetism
/.Ammeters are connected with the negative or black lead connected to the:
Select one:
a. positive side of the circuit
b. parallel side of the circuit
c. negative side of the circuit
d. switch of the circuit
/.The strength of the magnetic field produced in a shunt wound generator:
Select one:
a. is weak
b. is fairly constant
c. fluctuates
d. is regulated by an external AC supply
/.Three major losses which occur in a transformer are iron losses, copper losses and:
Select one:
a. cooling losses
b. heat losses
c. flux leakage
d. capacitive losses
/.A typical low voltage device would include:
Select one:
a. 600V 3 phase motor
b. 24 V DC motor
c. buzzers and doorbells
d. feeder services for large buildings
/.This type of circuit may be used to reduce energy and installation costs for seasonal
loads by using the same supply capacity for the loads alternately:
Select one:
a. overload switch
b. tie switch
c. transfer switch