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High voltage engineering objective interview questions part 1

1. Electrical conduction in gases was first studied in
A. Loeb
B. Maxwell
C. Townsend
D. None

Answer : c
Q.2 SF6 is a
A. Natural gas
B. Electronegative gas
C. Ionize gas
D. Non attaching gas
Ans : b

Must Read: Electrical Engineering Interview Questions

Q.3 Minimum sparking potential of air is
A. 40 v
B. 100 v
C. 4.4v
D. 325v
Answer : d

Q.4 The requirement of gases for insulation purpose is
A. High dielectric strength and thermal stability
B. High thermal stability
C. High dielectric strength only
D. None
Answer : A

Q.5 Transformer oil is
A. Askeral
B. Silicone oil
C. Polyster oil
D. Mineral oil
Answer: D

Q.6 The breakdown strength of mineral oil is about
A. 20kv/mm
B. 30-40 kv/mm
C. 50 kv/mm
D. None
Answer : B

Q.7 Dielectric constant of mineral oil is
A. 1.5 to 2.0
B. 2.2 to 2.4
C. 3.0 to 3.5
D. None
Answer : b

Q.8 maximum dielectric strength obtained with pureliquid
A. 100 kv/mm
B. 10 kv/mm
C. 1mv/mm
D. All
Answer :a

Q.9 which liquid has highest breakdown strength is
A. Mineral oil
B. Silicone oil
C. Polyolefins
D. None
Answer : b
Q. 10 conduction and breakdown in commercial liquids is affected by
A. Solid partical
B. Vapour
C. Electrode materials
D. All
Answer : d

If you face any problem with any question then comment below.
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