6) The speed of a d.c. motor can be controlled by varying its flux per pole orresistance of armature circuit.7) If the impedance triangles of two transformers operating in parallel are notidentical in shape and size, the two transformers will run with different power factors.8) In a DC motor, unidirectional torque is produced with the help of brushesand commutator.9) The ordinary efficiency of a given transformer is maximum when it runs athalf full-load.10) The series field of a short-shunt d.c. generator is excited by shunt currents.11) The speed of a d.c. motor can be controlled by varying its flux per pole orresistance of armature circuit.12) The primary and secondary windings of an ordinary 2-winding transformeralways have separate magnetic circuits.13) A 60 Kw DC four- pole generator has a lap winding if rotated in citrine speed thatgenerate 520 volts, the current flowing in each armature conductors is 22.5A .14) The function of The Armature is to rectify the internal ac generated voltage in theelectrical machines.v/r15) The critical resistance of the d.c. generator is the resistance of load.16) At no load, the generated voltage in a DC generator is small due to residual fieldflux .17) A transformer of voltage regulation (3.1%) is better than a transformer of (1.8 %)and the voltage regulation of ideal transformer is (unity).18) The eddy currents always tend to flow perpendicular to the flux.19) The magnetic field intensity is a vector quantity perpendicular to the direction offield density vector.20) The areas of the hysteresis loop is a measure of heat energy lost per cycle so thatchoosing the hard magnetic material is better for construction of magnetic circuits.

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6) The speed of a d.c. motor can be controlled by varying its flux per pole or resistance of armature circuit.

Introductory Circuit Analysis (13th Edition)

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Publisher:Robert L. Boylestad

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Concept explainers

Three Phase Induction Motor

The induction motor is an electric motor that runs on AC (alternating current) and it is of two type single phase motor that work on single-phase power supply and three-phase motor that work on three-phase power supply.

Question

6) The speed of a d.c. motor can be controlled by varying its flux per pole or
resistance of armature circuit.
7) If the impedance triangles of two transformers operating in parallel are not
identical in shape and size, the two transformers will run with different power factors.
8) In a DC motor, unidirectional torque is produced with the help of brushes
and commutator.
9) The ordinary efficiency of a given transformer is maximum when it runs at
half full-load.
10) The series field of a short-shunt d.c. generator is excited by shunt currents.
11) The speed of a d.c. motor can be controlled by varying its flux per pole or
resistance of armature circuit.
12) The primary and secondary windings of an ordinary 2-winding transformer
always have separate magnetic circuits.
13) A 60 Kw DC four- pole generator has a lap winding if rotated in citrine speed that
generate 520 volts, the current flowing in each armature conductors is 22.5A .
14) The function of The Armature is to rectify the internal ac generated voltage in the
electrical machines.
v/r
15) The critical resistance of the d.c. generator is the resistance of load.
16) At no load, the generated voltage in a DC generator is small due to residual field
flux .
17) A transformer of voltage regulation (3.1%) is better than a transformer of (1.8 %)
and the voltage regulation of ideal transformer is (unity).
18) The eddy currents always tend to flow perpendicular to the flux.
19) The magnetic field intensity is a vector quantity perpendicular to the direction of
field density vector.
20) The areas of the hysteresis loop is a measure of heat energy lost per cycle so that
choosing the hard magnetic material is better for construction of magnetic circuits.

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