31. Water gas generator is made of
Carbon steel-brick lined
Stainless steel-lead lined
Cast iron
High carbon steel-procelain lined
✅ The correct answer is option A.
Materials and Construction MCQs
32. Which of the following finds the least commercial use?
Pure iron
High silicon iron
Low carbon steel
High carbon steel
✅ The correct answer is option A.
33. Purity of electrical grade aluminium should be ≥ __________ percent.
95
99.5
85
90
✅ The correct answer is option B.
34. Ball bearings are generally made of
Plain carbon steel
Chrome carbon steel
Stainless steel
Malleable cast iron
✅ The correct answer is option B.
35. Fatigue strength of a material increases by
Having notches in the specimen
Rise in temperature
Under stressing the specimen
Having scratches on the surface
✅ The correct answer is option C.
36. Most suitable material of construction for the storage of concentrated nitric acid is
Cast iron
Monel
Karbate
Aluminium or chromium alloys (Cr > 18% for cold acid)
✅ The correct answer is option D.
37. Carbon content in plain carbon steel is __________ percent.
0.1 to 0.15
0.35 to 0.45
0.65 to 0.80
0.85 to 1.2
✅ The correct answer is option B.
38. Maximum carbon content in cast iron is __________ percent.
3.8
5.2
4.8
4.3
✅ The correct answer is option D.
39. Concrete tank can be used to store
Alum
Ferrous sulphate
Sulphuric acid
Saturated brine
✅ The correct answer is option D.
40. Which of the following contains maximum percentage of carbon?
Boiler plate steel
Rail steel
Saws for cutting steel
Railway spring steel
✅ The correct answer is option C.