In case of PVC cables the mechanical damage during excavation or by any other means may other means may cause a breaking of conductor or a short circuit between conductors of different phases or a short circuit between the conductor and earth. In case of PILC cables, a puncture of the lead sheath during excavation or by any vibration or by any chemical action of corrosive compounds of soil may cause an ingress of moisture resulting damage to the insulation and consequent short circuits. Defective conductors having uneven size and broken strand of conductors excessive drainage of impregnated oil due to the crack in lead shealth or improper end seals and deterioration of oil compound due to heating caused by dielectric losses or overload or poor heat dissipation or exposure to external heat source can be the causes of damage to the cable.
 Multiple Choice Question (MCQ) of Electronics page-17:241. Which of the following statement is true? a) The saturation voltage VCF of silicon transistor is more than germanium transistor. b) The saturation voltage VCE for germanium transistor is more than silicon transistor. c) The saturation voltage VCE for silicon transistor is same as that for germanium. d) The saturation voltage VCE for silicon transistor is lower than germanium transistor. |
Multiple Choice Question (MCQ) of Electronics page-16:226. Which of the following statement is correct? a) Inner electrons are always present in the semiconductor. b) Bound electrons are always present in the semiconductor. c) Free electrons are always present in the semiconductor. d) Inner and bound electrons are always present in the semiconductor. |
Multiple Choice Question (MCQ) of Electronics page-15:211. The materials whose electrical conductivity is usually less than 1 × 106 mho/m are a) Semiconductors b) Conductors c) Insulators d) Alloys |
Multiple Choice Question (MCQ) of Electronics page-14:196. In which of the following device the base resistors are not added in the package but added externally? a) UJT b) CUJT c) PUT d) None of the above |
Multiple Choice Question (MCQ) of Electronics page-13:181. The conduction in JEFT is always by the a) Majority carriers b) Minority carriers c) Holes d) Electrons e) Holes and electrons simultaneously |