The underground system cannot be operated above_________________?

Related Mcqs:

1. Which of the following methods is used for laying of underground cables ?

   A. Direct laying
   B. Draw-in-system
   C. Solid system
   D. All of the above

2. The material commonly used for sheaths of underground cables is______________?

   A. lead
   B. rubber
   C. copper
   D. iron

3. The current drawn by the line due to corona losses is___________?

   A. non-sinusoidal
   B. sinusoidal
   C. triangular
   D. square

4. Owing to skin effect:

   A. current flows through the half cross-section of the conductor
   B. portion of the conductor near the surface carries more current and core of the conductor carries less current
   C. portion of the conductor near the surface carries less current and core of the conductor carries more cur¬rent
   D. any of the above
   E. none of the above

5. For aluminium, as compared to copper, all the following factors have higher values except:

   A. specific volume
   B. electrical conductivity
   C. co-efficient of linear expansion
   D. resistance per unit length for same cross-section

6. For transmission of power over a distance of 500 km, the transmission voltage should be in the range?

   A. 150 to 220 kV
   B. 100 to 120 kV
   C. 60 to 100 kV
   D. 20 to 50 kV

7. The corona is considerably affected by which of the following _______________?

   A. Size of the conductor
   B. Shape of the conductor
   C. Surface condition of the conductor
   D. All of the above

8. 310 km line is considered as_______________?

   A. a long line
   B. a medium line
   C. a short line
   D. any of the above

9. Most of the high transmission lines in Pakistan are_______________?

   A. underground
   B. overhead
   C. either of the above
   D. none of the above

10. Which of the following is usually not the generating voltage ?

    A. 6.6 kV
    B. 8.8 kV
    C. 11 kV
    D. 13.2 kV