1. The starting voltage as compared to voltage during welding in manual metal arc welding is
a. same b. more c. less d. half
2. The ratio between the heat liberated at positive and negative poles in arc welding is
a. 1:1 b. 1:2 c.2:1 d. 2:3
3. The surface and sub-surface cracks in the weldment of magnetic alloys can be inspected by
a. X-ray radiography b. Eddy current testing c. Ultrasonic testing
d. Magnetic particle inspection
4. In electric welding, the supply voltage generally
a. les than the welding voltage b. same as the welding voltage c. more than the welding voltage d. none of these
5. Workshop safety is the responsibility of
a. employees only b. employers only c. employees and employers d. the work's committee
6. 116. The right way to detect the location of gas leak is to :
a. use a light match b. use a bucket of water c. use your sense of smell
d. use a brush and soap solution
7. If a worker has suffered from electric — shock, he should be :
a. given an alcoholic drink b. given a cold drink c. made to walk d. kept warm and covered
8. Which out of the following is a weld defect: a. heat-affected zone b. undercut
c. penetration bead d. fusion zone
9. Which two gases from the atmosphere must be prevented from entering the weld metal ?
a. oxygen and nitrogen b. nitrogen and argon c. oxygen and argon d. none of these
10. As compared to an air-cooled welding machine, an oil cooled welding machine has a:
a. higher duty cycle b. lower duty cycle c. same duty cycle d. none of these
11. Presence of slag on the surface of molten metal: 0
a. increase its rate of cooling b. decreases the rate of cooling C. normal rate of cooling
d.none of these
12. How is the arc normally restarted after it is broken ?
a. strike the arc again on the bead behind the crater and move ahead .
b. strike the arc again a little ahead of crater, work backward and then forward C
13. What may happen if slag is not removed from a bead before depositing another one on it?
a. entrapped slag will refine the weld metal b. entrapped slag will weaken the weld c none of these
14.The semi-circular deposit on the welded bead is called :
a. reinforcement b. crater c. sealing run d. none of these
15. The density of slag is :
a. more than that of molten metal b. less than that of molten metal
c. same as that of molten metal d. none of these
16. Shields and helmets are made dead block in color because
a. it gives pleasant appearance b. it increases reflection of light
c. it reduces reflection of light d. none of these
17. A depression formed at the end of weld bead is called :
a. reinforcement b. crater c. sealing run d. none of these
18. When not using, keep the electrode on a support which is:
a. insulator b. conductor c. crater d. none of these
19. The protective clothing of a welder loses its insulating property when it is :
a. dry b.wet c. conductor d. none of these
20. The metal arc welding process is
a. fusion welding b. resistance welding c. pressure welding d. forge welding
21. Walls and ceilings of welding shop should be painted such that it reflects :
a. very little ultra-violet rays b. very much ultra-violet rays
c. resistance welding d. none of these
22. A welding rectifier:
a. converts A.C. to D. C b. converts D.C to A.C
c. corrects current changes d. corrects voltage changes
23. Change of polarity is possible with :
a. A.C. only b. D.C only c. A.C and D.C both d. neither A.G nor D.C
24. The most likely reason for porosity to be caused is due to :
a. incorrect electrode manipulation b. too less current
c. too high current d. damp electrodes
25. One of the functions of electrode coating
a. to increase welding current b. to stabilize the arc c. to prevent rusting d. to control arc temperature