Verified Questions and Answers Study
Guide
Inductance is the property of the coil of a wire that opposes a change in____ in an
electromagnetic device. - Answer-current
TRUE or FALSE Ohm's Law states that when voltage is initially applied to a coil, the
induced voltage opposes the source voltage. - Answer-False
When voltage is initially applied to a coil, current is - Answer-Low
The induced voltage that opposes any change in current is called - Answer-CEMF
5. CEMF is greatest when the lines of flux are expanding or contracting at their
greatest or lowest rate of change. - Answer-Greatest
When conductors share magnetic lines of force, it is referred to as - Answer-
Mutual Inductance
,The BLANK can determine which direction a current-carrying conductor will move
in a magnetic field. - Answer-Right-hand rule
TRUE OR FALSE The elementary DC motor is constructed differently than a DC
generator. - Answer-False
A BLANK changes mechanical energy to electrical energy. - Answer-Generator
A BLANK changes electrical energy to mechanical energy. - Answer-Motor
TRUE OR FALSE The same DC machine may operate as either a generator or a
motor. - Answer-True
CRMF BLANK current flow in a rotating DC motor - Answer-Limits
BLANK can affect the amount of CEMF produced - Answer-Load
Lenz's Law states that an induced current is always in such a direction that its field
BLANK the action that produced it. - Answer-Opposes
Lenz's Law explains the results of the magnetic field's attempt to correct BLANK
caused by conflicting fields. - Answer-Distortion
The BLANK or BLANK on DC machines serves as the overall support. - Answer-
Frame or Yoke
, TRUE OR FALSE The main frame serves as a magnetic circuit path. - Answer-True
TRUE OR FALSE Magnetic flux is only present in the field. - Answer-False
Pole pieces are made of thin layers of iron or steel called BLANK - Answer-
Laminations
Field windings and pole pieces together are called the BLANK - Answer-Field
TRUE OR FALSE Series field windings consist of many turns of fine wire. - Answer-
False
TRUE OR FALSE Shunt field windings consist of many turns of fine wire. - Answer-
True
TRUE OR FALSE A DC machine may have one or three poles. - Answer-False
Two ways of connecting field windings are called BLANK and BLANK. - Answer-
Series; Shunt
TRUE OR FALSE Interpoles can be added to increase armature reaction. - Answer-
False
The portion of the machine supporting the brush rigging is called the BLANK -
Answer-End bell