11.In which of the following processes, heat is created by blacksmith fire?
a) Forge welding .
b) Spot welding
c) Projection welding .
d) Seam welding
12.Is it necessary to apply pressure in submerged arc welding?
a) Yes
b) No
c) Sometimes
d) None of these
13.Which one of the following welding process requires the use of flux?
a) TIG
b) MIG
c) SAW
d) MAG
14.What is an “inert gas” as used in MIG welding?
a) A gas that cools the weld zone to prevent cracking
b) A gas that prevents porosity by burning a hot neutral flame
c) A gas that does not chemically react with other elements to help produce a quality weld
d) A gas that heats up the weld zone to create better quality weld
15. The flux used in electro slag welding has .
a) Low electrical resistance
b) Medium electrical resistance
c) High electrical resistance
d) No electrical resistance
16.Which one of the following is NOT the characteristic of electro slag welding?
a) Itresults in coarse grain structure of the weld
b) It results in low toughness of the weld
c) It is done in vertical position
d) Its welding speed is slow
17.Atomic hydrogen welding will have a temperature of
a) 2400° C
b) 3200° C
c) 6100° C
d) 1600° C
18.Which statement applies to thermit welding?
a) Itis hazardous due to very high temperature
b) Once this process is initiated it con not be smoothened
c) This process can be considered to be a portable foundry
d) All of these
19.When two wires of different metals are twisted together and heat applied to the junction,
an e.m.f. is produced. This effect is used in a thermocouple to measure.
a) e.m.f
b) Temperature
c) Expansion
d) Heat
20.Increase in carbon content of the metal will
a) Increase hardnéess and strength
b) Improve ductility and toughness
c) Reduce weldability
d) Both (a) & (c)