Electrical Cables Multiple Choice Questions and Answers

31. The bedding on a cable consists of

1. hessian cloth
2. jute
3. any of the above
4. none of the above

32. The breakdown of insulation of the cable can be avoided economically by the use of

1. inter-sheaths
2. insulating materials with different dielectric constants
3. both a and b
4. none of the above

33. The breakdown voltage of a cable depends on

1. presence of moisture
2. working temperature
3. time of application of the voltage
4. all of the above

34. The current carrying capacity of cables in D.C. is more thanthat in A.C. mainly due to

1. absence of harmonics
2. non-existence of any stability limit
3. smaller dielectric loss
4. absence of ripples

35. The disadvantage with paper as insulating material is

1. it is hygroscopic
2. it has high capacitance
3. it is an organic material
4. none of the above

36. The electrostatic stress in underground cables is

1. same at the conductor and the sheath
2. minimum at the conductor and maximum at the sheath
3. maximum at the conductor and minimum at the sheath
4. zero at the conductor as well as on the sheath

37. The insulating material for a cable should have

1. low cost
2. high dielectric strength
3. high mechanical strength
4. all of the above

38. The insulating material for cables should

1. be acid proof
2. be non-inflammable
3. be non-hygroscopic
4. have all above properties

39. The insulating material should have

1. low permittivity
2. high resistivity
3. high dielectric strength
4. all of the above

40. The insulation of the cable decreases with

1. the increase in length of the insulation
2. the decrease in the length of the insulation
3. either a or b
4. none of the above