Top 150+ Solved DC Generators MCQ Questions Answer
Q. PVC stands for
a. polyvinyl chloride
b. post varnish conductor
c. pressed and varnished cloth
d. positive voltage conductor
Q. In the cables, the location of fault is usually found out by comparing
a. the resistance of the conductor
b. the inductance of conductors
c. the capacitances of insulated conductors
d. all above parameters
Q. In capacitance grading of cables we use a ______ dielectric.
a. composite
b. porous
c. homogeneous
d. hygroscopic
Q. The material for armouring on cable is usually
a. steel tape
b. galvanised steel wire
c. any of the above
d. none of the above
Q. The relative permittivity of rubber is
a. between 2 and 3
b. between 5 and 6
c. between 8 and 10
d. between 12 and 14
Q. Solid type cables are considered unreliable beyond 66 kV because
a. insulation may melt due to higher temperature
b. skin effect dominates on the conduc¬tor
c. of corona loss between conductor and sheath material
d. there is a danger of breakdown of insulation due to the presence of voids
Q. If the length of a cable is doubled, its capacitance
a. becomes one-fourth
b. becomes one-half
c. becomes double
d. remains unchanged
Q. In cables the charging current
a. lags the voltage by 90°
b. leads the voltage by 90°
c. lags the voltage by 180°
d. leads the voltage by 180°
Q. A certain cable has an insulation of relative permittivity 4. If the insulation is replaced by one of relative permittivity 2, the capacitance of the cable will become
a. one half
b. double
c. four times
d. none of the above
Q. If a cable of homogeneous insulation has a maximum stress of 10 kV/mm, then thedielectric strength of insulation should be
a. 5 kV/mm
b. 10 kV/mm
c. 15 kV/mm
d. 30 kV/mm
Q. In the cables, sheaths are used to
a. prevent the moisture from entering the cable
b. provide enough strength
c. provide proper insulation
d. none of the above