99. In inter gas arc welding following is used for welding magnesium
A.Non-combustible electrode in combination with helium and d.c. current
B.Combustible electrodes and argon in combination with a.c. current
C.Straight polarity d.c. current
D.Carbon dioxide, because of its excellent penetration and high speed
100. Oxygen to acetylene ratio in case of neutral flame is
A.0.8 : 1
B.1 : 1
C.1.2 : 1
D.2 : 1
101. In inert gas arc welding, following is used for welding aluminium
A.Non-combustible electrode in combination with helium and d.c. current
B.Combustible electrode and argon in combination with a.c. current
C.Straight polarity d.c. current
D.Carbon dioxide, because of its excellent penetration and high seed
102. In metallic arc welding, the transfer of metal from the electrode is due to
A.Molecular attraction
B.Surface tension and attraction
C.Gravitational force
D.Both (A) and (B) above
103. In which of the following welding techniques, the weld pool is surrounded by an inert gas
A.Arc welding
B.Carbon arc
C.MIG
D.Electroslag welding
104. The striking voltage as compared to voltage during welding in arc welding is
A.Same
B.More
C.Less
D.Unpredictable
105. In inert gas arc welding, following is used for welding carbon steel
A.Non-combustible electrode in combination with helium and d.c. current
B.Combustible electrodes and argon in combination with a.c. current
C.Straight polarity d.c. current
D.Carbon dioxide, because of its excellent penetration and high speed
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