Top 150+ Solved Design of Electrical Machines MCQ Questions Answer
Q. Which of the following is the major consideration to evolve a good design ?
a. Cost
b. Durability
c. Compliance with performance criteria as laid down in specifications
d. All of the above
Q. The efficiency of a machine should be as ______ as possible to reduce the operatingcost.
a. high
b. low
c. either of the above
d. none of the above
Q. If an insulating material is operated beyond the maximum allowable temperature, itslife is
a. drastically increased
b. drastically reduced
c. unaffected
d. none of the above
Q. The design of mechanical parts is particularly important in case of _____ speedmachines.
a. low
b. medium
c. high
d. any of the above
Q. In induction motors, the length of air gap in kept as small as mechanically possible isorder to have
a. low power factor
b. high power factor
c. high over load capacity
d. any of the above
Q. In ______ machines, the size of the shaft is decided by the critical speed which dependson the deflection of the shaft.
a. small
b. medium
c. large
d. any of the above.
Q. The length cf air gap to be provided in ______ is primarily determined by power factorconsideration.
a. d.c. series motor .
b. d.c. shunt motor
c. induction motor
d. synchronous motor
Q. Electrical machines having a power output upto about 750 W may becalled_______machines.
a. small size
b. medium size
c. large size
d. any of the above
Q. Electrical machines having power outputs ranging from a few kW upto approximately250 kW may be classified as
a. small size machines
b. medium size machines
c. large size machines
d. any ofthe above
Q. Commercial available medium size machines have a speed range of ______ .
a. 200 to 400 r.p.m.
b. 600 to 1000 r.p.m.
c. 1000 to 1500 r.p.m.
d. 2000 to 2500 r.p.m.
Q. The action of electromagnetic machines can be related to which ofthe following basicprinciples ?
a. Induction
b. Interaction
c. Alignment
d. All of the above
Q. The change in flux linkages can be caused in which ofthe following ways ?
a. The flux is constant with respect to time and is stationary and the coil moves throughnit
b. The coil is stationary with respect to flux and the flux varies in magnitude with respect to time
c. Both the changes mentioned above occure together, i.e., the coil moves through a time varying field
d. All ofthe above
Q. is universally used for windings of electrical machines because it is easily workablewithout any possibility of fracture.
a. Silver
b. Steel
c. Aluminium
d. Copper
Q. Aluminium when adopted as a conductor material in ______ transformers, decreases theoverall cost of the transformer
a. small size
b. medium size
c. large size
d. any of the above size