Cable mcq part -1

1. The insulating material for a cable should have
(a) low cost
(b) high dielectric strength
(c) high mechanical strength
(d) all of the above

Ans: d

2. Which of the following protects a cable against mechanical injury ?
(a) Bedding
(b) Sheath
(c) Armouring
(d) None of the above

Ans: c

3. Which of the following insulation is used in cables ?
(a) Varnished cambric
(b) Rubber
(c) Paper
(d) Any of the above

Ans: d

4. Empire tape is
(a) varnished cambric
(b) vulcanised rubber
(c) impregnated paper
(d) none of the above

Ans: a

5. The thickness of the layer of insulation on the conductor, in cables, depends upon
(a) reactive power
(b) power factor
(c) voltage
(d) current carrying capacity

Ans: c

6. The bedding on a cable consists of
(a) hessian cloth
(b) jute
(c) any of the above
(d) none of the above

Ans: c

7. The insulating material for cables should
(a) be acid proof
(b) be non-inflammable
(c) be non-hygroscopic
(d) have all above properties

Ans: d

8. In a cable immediately above metallic sheath is provided.
(a) earthing connection
(b) bedding
(c) armouring
(d) none of the above

Ans: b

9. The current carrying capacity of cables in D.C. is more thanthat in A.C. mainly due to
(a) absence of harmonics
(b) non-existence of any stability limit
(c) smaller dielectric loss
(d) absence of ripples
(e) none of the above

Ans: c

10. In case of three core flexible cable the colour of the neutral is
(a) blue
(b) black
(c) brown
(d) none of the above

Ans: a

11 cables are used for 132 kV lines.
(a) High tension
(b) Super tension
(c) Extra high tension
(d) Extra super voltage

Ans: d

12. Conduit pipes are normally used to protect cables.
(a) unsheathed cables
(b) armoured
(c) PVC sheathed cables
(d) all of the above

Ans: a

13. The minimum dielectric stress in a cable is at
(a) armour
(b) bedding
(c) conductor surface
(d) lead sheath

Ans: d

14. In single core cables armouring is not done to
(a) avoid excessive sheath losses
(b) make it flexible
(c) either of the above
(d) none of the above

Ans: a

15. Dielectric strength of rubber is around
(a) 5 kV/mm
(b) 15 kV/mm
(c) 30 kV/mm
(d) 200 kV/mm

Ans: c

16. Low tension cables are generally used upto
(a) 200 V
(b) 500 V
(c) 700 V
(d) 1000 V

Ans: d

17. In a cable, the maximum stress under operating conditions is at
(a) insulation layer
(b) sheath
(c) armour
(d) conductor surface

Ans: d

18. High tension cables are generally used upto
(a) 11kV
(b) 33kV
(c) 66 kV
(d) 132 kV

Ans: a

19. The surge resistance of cable is
(a) 5 ohms
(b) 20 ohms
(c) 50 ohms
(d) 100 ohms

Ans: c

20. PVC stands for
(a) polyvinyl chloride
(b) post varnish conductor
(c) pressed and varnished cloth
(d) positive voltage conductor
(e) none of the above

Ans: a