Yes, it can be made from those materials.No, it cannot be made from lead, lead alloy, or aluminium.Only lead is used for the metallic sheath.Only aluminium is used for the metallic sheath.The metallic sheath is made from copper.

4.What happens to the capacitance of a cable when its length is increased to twice its original size?

reduces to one-quarterreduces to halfincreases to twice the originalstays the same

5.What is the primary purpose of sheaths in electrical cables?

to stop moisture from penetrating the cableto offer mechanical strengthto ensure adequate insulationnone of these

6.Which method is the most cost-effective way to prevent the insulation of a cable from deteriorating?

Using interlayer sheathsEmploying insulating materials with varying dielectric propertiesCombining both interlayer sheaths and diverse insulating materialsNone of the listed methods

7.What is the primary purpose of intersheaths in electrical cables?

to reduce mechanical stressto eliminate the need for high-quality insulationto ensure even distribution of electrical stressnone of these

8.For a cable with uniform insulation experiencing a peak electric stress of 10 kV/mm, what should be the dielectric strength of the insulation?

5 kV per millimeter10 kV per millimeter15 kV per millimeter30 kV per millimeter20 kV per millimeter

9.In electrical cables, how does the charging current relate to the voltage in terms of phase angle?

The current lags the voltage by 90 degreesThe current leads the voltage by 90 degreesThe current lags the voltage by 180 degreesThe current leads the voltage by 180 degreesThe current is in phase with the voltage

10.Why are solid type cables considered unsuitable for use above 66 kV voltage levels?

The insulation can melt when exposed to elevated temperatures.The conductor experiences significant skin effect at higher voltages.Corona discharge occurs between the conductor and the surrounding sheath.Insulation breakdown is likely due to voids present within the material.

11.A cable originally has insulation with a relative permittivity of 4. If this insulation is substituted with material having a relative permittivity of 2, how will the cable's capacitance change?

It will reduce to halfIt will increase to twice its original valueIt will become four times largerThere will be no changeIt will triple

How to prepare with Cables MCQs

Work through questions topic by topic, then revisit any you answered incorrectly.
Read explanations carefully—they often cover facts that repeat across PPSC, FPSC, and NTS papers.
Pair subject practice with past papers to see how Cables appears in real exam conditions.

Cables

About this subject

Practice questions

1.Is the 'draw-in system' commonly used for installing underground cables in densely populated regions where digging is costly and troublesome?

2.Are oil-filled cables challenging to maintain?

3.Can the metallic sheath be constructed from lead, lead alloy, or aluminium?

4.What happens to the capacitance of a cable when its length is increased to twice its original size?

5.What is the primary purpose of sheaths in electrical cables?

6.Which method is the most cost-effective way to prevent the insulation of a cable from deteriorating?

7.What is the primary purpose of intersheaths in electrical cables?

8.For a cable with uniform insulation experiencing a peak electric stress of 10 kV/mm, what should be the dielectric strength of the insulation?

9.In electrical cables, how does the charging current relate to the voltage in terms of phase angle?

10.Why are solid type cables considered unsuitable for use above 66 kV voltage levels?

11.A cable originally has insulation with a relative permittivity of 4. If this insulation is substituted with material having a relative permittivity of 2, how will the cable's capacitance change?

12.Up to what voltage level are pressure cables typically utilized?

13.What is the approximate range of the relative permittivity for rubber?

14.Which of the following materials is commonly used for cable armouring?

15.Conduit pipes are typically employed to safeguard which type of cables?

16.What does the abbreviation PVC represent?

17.Which type of dielectric is utilized in capacitance grading of cables?

18.What is the typical surge resistance value of a cable?

19.Where is the lowest dielectric stress observed within a cable?

20.When locating a fault in cables, which parameter is typically compared to identify the fault position?

How to prepare with Cables MCQs

More on PakQuizHub