1) Lead pipes are not safe for carrying drinking water, because water, containing dissolved oxygen attacks lead thereby forming poisonous Pb(OH)2. Lead pipes are readily corroded by___________________? a. Dilute HCl b. Acetic acid c. Concentrated H2SO4 d. None of these
|
||||
2) Nickel as a material of construction__________________? a. Is used as an alloying element for both ferrous & non-ferrous alloys b. Is paramagnetic below 415° C (its Curie temperature) c. Diamagnetic d. Has a body centred cubic (bcc) crystal lattice structure
|
||||
3) Tin base and lead base alloys are used for bearing materials. Tin compared to lead has lower_________________? a. Price b. Corrosion resistance c. Thermal conductivity d. Abundant availability
|
||||
4) Glass is corroded by________________? a. Fluorine (dry or wet) b. Sulphuric acid c. Phosphoric acid d. None of these
|
||||
5) Nickel base alloys with ______________ are known as monel metal? a. Zinc b. Tin c. Copper d. Molybdenum
|
||||
6) How many atoms are there per unit cell in a body centred cubic lattice system ? a. 6 b. 5 c. 3 d. 2
|
||||
7) Bush bearings are made of______________________? a. Mild steel b. Phosphorous bronze c. White metal alloys d. None of these
|
||||
8) Presence of cobalt in steel improves its____________________? a. Cutting ability b. Corrosion resistance c. Tensile strength d. None of these
|
||||
9) A hardness depth of about 3 mm can be achieved by induction hardness in ______________ seconds? a. 5 b. 100 c. 250 d. 500
|
||||
10) Wrought iron is having very high ________________? a. Hardness b. Strength c. Corrosion resistance d. Susceptibility to changes in its properties by heat treatment
|
||||
11) Rotary kilns in cement industry are lined with _____________bricks? a. Fireclay b. Silica c. Lead d. High alumina & high magnesia
|
||||
12) Post weld heat treatment is done by____________________? a. Normalising b. Stress relieving c. Tempering d. Solution annealing
|
||||
13) High speed steel tools retain their hardness upto a temperature of _____________ °C? a. 500 b. 750 c. 900 d. 1100
|
||||
14) When iron is rusted, it is__________________? a. Converted to a fine powder b. Reduced c. Oxidised d. None of these
|
||||
15) Caustic soda is transported in _____________ lined containers ? a. Glass b. Nickel c. Neoprene d. Either B. or C.
|
||||
16) _______________ is a donor impurity for semi-conductors ? a. Boron b. Antimony c. Gallium d. None of these
|
||||
17) Non-ferrous metals and hard steels do not exhibit a definite yield point, when pulled in the testing machine and hence for these cases, a better measure of their elastic properties is defined by the ______________ stress? a. Ultimate b. Yield point c. Proof d. None of these
|
||||
18) How many molecules per unit cell are there in a face centred cubic lattice ? a. 2 b. 4 c. 6 d. 8
|
||||
19) ‘Semi steel’ is__________________? a. Produced by adding 10-20% steel to the cupola charge b. Stronger than cast iron c. Both A. and B. d. Neither A. nor B.
|
||||
20) Which one occupies the lowermost position in the electromotive series of metals ? a. Aluminium b. Noble metals (Ag, Pt, Au) c. Zinc d. Alkali metals (K, Na, Li)
|
||||
21) Ferric stainless steels compared to austenitic stainless steels________________? a. Have lower corrosion resistance b. Are harder to fabricate c. Are less ductile and hence less suitable for cold pressing d. All A., B. and C.
|
||||
22) Reduction in the grain size reduces the _______________ of the material? a. Fatigue resistance b. Tensile strength c. Creep resistance d. All A., B. & C.
|
||||
23) ______________ iron is produced, when molten pig iron is allowed to cool gradually? a. White cast b. Grey cast c. Wrought d. None of these
|
||||
24) Sulphuric acid is mixed with ground phosphate rock (to produce phosphoric acid) in a steel digestor lined with__________________? a. Acidic refractory b. Rubber c. Karbate d. Lead or acid-proof bricks
|
||||
25) Maximum carbon content in cast iron is ______________ percent? a. 3.8 b. 5.2 c. 4.8 d. 4.3
|
||||
26) Cast iron is__________________? a. Used for making shock resisting parts b. Manufactured in cupola and is brittle c. Having compressive strength more than its tensile strength d. All A., B. & C.
|
||||
27) Sulphuric acid is mixed with ground phosphate rock (to produce phosphoric acid) in a steel digestor lined with______________? a. Acidic refractory b. Rubber c. Karbate d. Lead or acid proof bricks
|
||||
28) Manganese in steel affects its__________________? a. Ductility b. Tensile strength c. Hardness d. None of these
|
||||
29) High carbon steel contains more than _____________ percent carbon? a. 0.5 b. 2.2 c. 2.5 d. 2.8
|
||||
30) Which of the following has no effect on the carbide forming tendency in steels ? a. Molybdenum b. Phosphorus c. Chromium d. Vanadium
|