11. Which of the following D.C. distribution system is the simplest and lowest in first cost?

Radial system
Ring system
distribution system is the simplest and lowest in first cost? A. Radial system B. Ring system C. Interconnected system
None of the above

Detailed SolutionWhich of the following D.C. distribution system is the simplest and lowest in first cost?

12. Which of the following faults is most likely to occur in cables?

Cross or short-circuit fault
Open circuit fault
Breakdown of cable insulation
All of the above

Detailed SolutionWhich of the following faults is most likely to occur in cables?

13. The operating voltage of extra high tension cables is upto

6.6 kV
11 kV
33 kV
66 kV

Detailed SolutionThe operating voltage of extra high tension cables is upto

14. The usual spans with R.C.C. poles are

40-50 meters
60-100 meters
poles are A. 40-50 meters B. 60-100 meters C. 80-100 meters
300-500 meters

Detailed SolutionThe usual spans with R.C.C. poles are

15. Skin effect is proportional to

$${left( {{ ext{conductor diameter}}} ight)^{ rac{1}{2}}}$$
(conductor diameter)4
(conductor diameter)2
(conductor diameter)3 E. none of the above

Detailed SolutionSkin effect is proportional to

16. The presence of ozone due to corona is harmful because it

Reduces power factor
Corrodes the material
Gives odour
Transfer energy to the ground

Detailed SolutionThe presence of ozone due to corona is harmful because it

17. High voltage transmission lines use

Suspension insulators
Pin insulators
Both (A) and (B)
None of the above

Detailed SolutionHigh voltage transmission lines use

18. The wooden poles well impregnated with creosote oil or any preservative compound has life

From 2 to 5 years
10 to 15 years
25 to 30 years
60 to 70 years

Detailed SolutionThe wooden poles well impregnated with creosote oil or any preservative compound has life

19. The material commonly used for insulation in high voltage cables is

Lead
Paper
Rubber
None of the above

Detailed SolutionThe material commonly used for insulation in high voltage cables is

20. The material generally used for armour of high voltage cables is

Aluminium
Steel
Brass
Copper

Detailed SolutionThe material generally used for armour of high voltage cables is