MCQ
41. The transistor is made of--
silver
gold
copper
germanium
42. Which of the following iron exists between Type equation here.910°C and 1403°C?
∝-iron
δ -iron
β-iron
γ-iron
43. Solder is an alloy consisting of--
tin, antimony, copper
tin and lead
tin and copper
lead and zinc
44. Inconel is an alloy of--
nickel, chromium and iron
nickel, copper
nickel, chromium
nickel, zinc
45. Brass contains--
70% copper and 30% zinc
90% copper and 10% tin
85-92% copper and rest tin with little lead and nickel
70-75% copper and rest tin
46. The basic constituents of Hastelloy are--
aluminium, copper etc.
nickel, molybdenum etc.
nickel, copper, etc
all of the above
47. Nickel in steel—
improves wear resistance, cuttinability and toughness
refines grain size and produces les tendency to carburisation, improve corrosion and heat resistant proper ties
improves cutting ability and reduce hardenability
gives ductility, toughness, tensile strength and anti-corrosion property
48. Ductile cast iron—
contains 1.7 to 3.5% carbon in free state and is obtained by the slow cooling of molten cast iron
is also known as chilled cast iron and is obtained by cooling rapidly. It is almost non-machinable
is produced by annealing process. It is soft, tough and easily machined metal
is produced by small additions of magnesium (or creium) in the ladle Graphite is in nodular or spheroidal form and is well dispersed throughout the material
49. Eutectoid steel contains following percentage of carbon—
0.02%
0.3%
0.63%
0.8%
50. Basic constituents of Monel metal are--
nickel, copper
nickel, molybdenum
zinc, tin, lead
nickel, lead and tin
51. Austenite is a combination of--
ferritc and cementite
cementite and gamma iron
ferrite and austenite
ferrite and iron graphite
52. Machining properties of steel are improved by adding--
sulphur, lead, phosphorous
silicon, aluminium, titanium
vanadium, aluminium
chromium, nickel
53. Nodular iron has--
high machinability
low melting point
high tensile strength
all of the above.
54. Surveying tapes are made of a material having low coefficient of expansion and enough strength. The alloy used is—
silver metal
duralumin
Hastelloy
Invar
55. The most effective inhibitor of grain growth. when added in small quantities is--
carbon
manganese
vanadium
Cobalt
56. Tensile strength of steel can be safely increased by--
adding carbon up to 2.8%
adding carbon up to 6.3%
adding carbon up to 0.83%
adding small quantities of copper
57. Grey cast iron--
contains 1.7 to 3.5% carbon in free state and is obtained by the slow cooling of molten
is also known as chilled cast iron and is obtained by cooling rapidly. It is almost non-machinable
is produced by annealing process. It is soft, tough and easily machine metal
is produced by small additions of magnesium (or cerium) in the ladle. Graphite is in nodular or spheroida form and is well dispersed throughout the material
58. The cutting tools are made from--
nickel steel
silicon steel
chrome steel
high speed steel
59. Cobalt in steel—
improves wear resistance, cuttinability and toughness
refines grain size and produces les tendency to carburisation, improve corrosion and heat resistant proper ties
improves cutting ability and reduce hardenability
gives ductility, toughness, tensile strength and anti-corrosion property
60. The percentage of carbon in low carbon steel is—
0.05%
0.15%
0.3%
0.5%