Chapter 5: Transformers Exam UPDATED
QUESTIONS AND CORRECT ANSWERS
Current transformers step down the current rather than the:
Select one:
a. resistance
b. voltage
c. conductance
d. number of poles - CORRECT ANSWER b
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 - CORRECT ANSWER c
What are the microscopic magnetic particles called:
Select one:
a. hysteresis
b. eddy currents
c. conductor reluctance
d. domains - CORRECT ANSWER d
A transformer has a primary voltage of 500 volts and 20 turns on the primary winding. If the
secondary winding has 5 turns the voltage of the secondary is:
Select one:
a. 2000 volts
b. 2500 volts
,c. 125 volts
d. 100 volts - CORRECT ANSWER c
Iron losses in transformers are caused by:
Select one:
a. hysteresis
b. eddy currents
c. flux leakage
d. all of the above - CORRECT ANSWER d
A device used to change the voltage and current from one level to another, is known as a/an:
Select one:
a. conductor
b. resistor
c. alternator
d. transformer - CORRECT ANSWER d
According to ANSI, what is the oils maximum operating temperature of a transformer:
Select one:
a. 30C
b. 60C
c. 90C
d. 100C - CORRECT ANSWER c
Who is responsible for the electrical supply service equipment?:
Select one:
a. manufacture
b. utility company
c. industry owner
d. provincial government - CORRECT ANSWER b
, Transformers used to stepdown high voltage to low voltage (120V MAXIMUM) are:
Select one:
a. current transformer
b. K transformer
c. potential transformer
d. step up transformer - CORRECT ANSWER c
What are the microscopic magnetic particles called:
Select one:
a. hysteresis
b. eddy currents
c. conductor reluctance
d. domains - CORRECT ANSWER d
A transformer has a primary voltage of 440 volts and 20 turns on the primary winding. If the
secondary winding has 10 turns the voltage of the secondary is:
Select one:
a. 220 volts
b. 200 volts
c. 880 volts
d. 22 volts - CORRECT ANSWER a
A transformer works on the principle of:
Select one:
a. reverse polarity
b. electromagnetic induction
c. DC power flowing in one direction
d. straight polarity - CORRECT ANSWER b