Questions With Complete Solutions
__________ current flow is from positive to negative.
a. Electron
b. Static
c. Conventional
d. Generated
e. Reversed Correct Answers c. Conventional
__________ is an electromotive force.
a. Power
b. Amperage
c. The ohm
d. The watt
e. The volt Correct Answers e. The volt
__________________ are used on DC motors and generators to
set up a magnetic field.
a. Transformers
b. Field poles
c. Insulated wires
d. Mica strips
e. Carbon rings Correct Answers b. Field poles
A 120/208 volt system is best described as a:
a. Two phase wye connected two-wire system
b. Three phase three-wire system
,c. Two phase delta connected two-wire system
d. Three phase wye connected four-wire system
e. Two phase delta connected three-wire system Correct
Answers d. Three phase wye connected four-wire system
A 120V/240V single phase system:
a. Is not used for heating elements
b. Can power a 3 phase motor
c. Has 2 wires energized from the source and a white or
grounded wire
d. Is not used in Canada
e. Has 3 wires energized from the source and a white or
grounded wire Correct Answers c. Has 2 wires energized from
the source and a white or grounded wire
A 4 pole alternator producing 60 Hz power must turn at:
a. 1200 rpm
b. 2400 rpm
c. 1800 rpm
d. 600 rpm
e. 1000 rpm Correct Answers c. 1800 rpm
A basic law of electricity is, unlike charges attract each other
and like charges:
a. repel each other
b. attract each other
c. reduce power output
d. hold each other
,e. are neutralized Correct Answers a. repel each other
A clamp-on ammeter measures current flow by using:
a. differential current flow between two conductors
b. electromagnetism
c. differential voltage
d. a portion of circuit resistance
e. a basic transformer principle Correct Answers e. a basic
transformer principle
A closed electrical circuit will:
a. be series only
b. contain an open switch or relay contact
c. not allow current to flow
d. be parallel only
e. allow current to flow Correct Answers e. allow current to
flow
A common use for a DC generator is:
a. An automobile alternator
b. Power supply for an elevator
c. Power supply for a machinist lathe
d. Power factor correction
e. Computer room power supply Correct Answers b. Power
supply for an elevator
, A compound wound DC generator has a combination of shunt
and characteristics, depending on the predominance of each type
of winding.
a. resistive
b. series
c. reverse wound
d. parallel
e. AC Correct Answers b. series
A compound wound DC generator may have three
characteristics which a:
1- decreasing output voltage versus load
2- no amperage requirement
3- constant output voltage
4- supplementary AC requirement
5- rising output voltage versus load:
a. 1, 2, 4
b. 1, 4, 5
c. 2, 3, 4
d. 2, 3, 5
e. 1, 3, 5 Correct Answers e. 1, 3, 5
A conductor supplied with current while in a magnetic field will:
a. tend to move at right angles to the flux lines
b. tend to remain stationary
c. want to move with the flux lines
d. form a solenoid