A. avoid excessive sheath losses
B. make it flexible
C. either of the above
D. none of the above
Related Mcqs:
- 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 - The current carrying capacity of cables in D.C. is more than that in A.C. mainly due to__________?
A. absence of harmonics
B. non-existence of any stability limit
C. smaller dielectric loss
D. absence of ripples
E. none of the above - The insulating material for cables should____________?
A. be acid proof
B. be non-inflammable
C. be non-hygroscopic
D. have all above properties - Cables, generally used beyond 66 kV are___________?
A. oil filled
B. S.L. type
C. belted
D. armoured - In capacitance grading of cables we use a _______ dielectric?
A. composite
B. porous
C. homogeneous
D. hygroscopic - Solid type cables are considered unreliable beyond 66 kV because___________?
A. insulation may melt due to higher temperature
B. skin effect dominates on the conductor
C. of corona loss between conductor and sheath material
D. there is a danger of breakdown of insulation due to the presence of voids - 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° - In congested areas where excavation is expensive and inconvenient ‘draw in system’ of laying of underground cables is often adopted
A. Yes
B. No - The thickness of metallic shielding on cables is usually_______________?
A. 0.04 mm
B. 0.2 to 0.4 mm
E. 3 to 5 mm
D. 40 to 60 mm - Underground cables are laid at sufficient depth___________?
A. to minimise temperature stresses
B. to avoid being unearthed easily due to removal of soil
C. to minimize the effect of shocks and vibrations due to gassing vehicles, etc
D. for all of the above reasons
