mechanical engineering MCQs – Page 84

Practise multiple-choice questions from mechanical engineering for competitive examinations and subject revision. Review each marked answer and report any item that may be outdated or unclear.

mechanical engineering Mcqs

1. compressors gas turbines and jet engines 2. theory of machines 3. nuclear power plants 4. engineering materials 5. strength of materials mechanical engineering 6. thermodynamics 7. heat transfer 8. i c engines 9. steam boilers engines nozzles and turbines 10. engineering mechanics 11. fluid mechanics mechanical engineering 12. production technology 13. machine design 14. hydraulic machines 15. workshop technology 16. refrigeration and air conditioning

1661. Killed steels are those steels__________________?
0

A. which are deoxidised in the ladle with silicon and aluminium

B. which are destroyed by burning

C. which after their destruction are recycled to produce fresh steel

D. in which carbon is completely burnt

E. which have poor properties due to improper manufacturing

1662. Perminvar alloy having constant permeability is an alloy of________________?
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A. nickel, copper and zinc

B. iron, zinc and bismuth

C. copper, nickel and antimony

D. antimony, copper and zinc

E. nickel, copper and iron

1663. The most effective inhibitor of grain growth, when added in small quantities is__________________?
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A. cobalt

B. vanadium

C. copper

D. manganese

E. carbon

1664. The units of kinematic viscosity are____________________?
0

A. kg sec/metre

B. newton-sec per metre

C. none of the above

D. newton-sec per metre

E. metres2 per sec

1665. Large forgings, crank shafts, axles normally contain carbon up to________________?
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A. 0.20 to 0.45%

B. 0.55 to 1.0%

C. 0.05 to 0.20%

D. 0.45 to 0.55%

E. 1.0 to 1.2%.

1666. The value of mass density in kgsecVm4 for water at 0C is_________________?
0

A. 91

B. 101.9

C. 1

D. 1000

E. 100

1667. Increase in pressure at the outer edge of a drum of radius R due to rotation at corad/sec, full of liquid of density p will be___________________?
0

A. 2pa2R2

B. pco2/?2/2

C. none of the above

D. pco2/?2

E. pa2R/2

1668. Nodular iron has____________________?
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A. good fluidity

B. high maehinability

C. high tensile strength

D. low melting point

E. all of the above

1669. Bell metal contains_____________________?
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A. 70-75% copper and rest tin

B. 70-75% copper and rest zinc and tin

C. 70% copper and 30% zinc

D. 85-92% copper and rest tin with little lead and nickel

E. 90% copper and 10% tin

1670. Cold rolled steel sheets contain carbon of the following order___________________?
0

A. 0.80%

B. 0.60%

C. 0.20%

D. 0.1%

E. 0.40%

1671. Ratio of inertia force to elastic force is known as__________________?
0

A. none of the above

B. Froude number

C. Reynolds number

D. Webers number

E. Mach number

1672. Ductile cast iron___________________?
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A. none of the above

B. is also known as chilled cast iron and is obtained by cooling rapidly. It is almost unmachinable

C. is produced by annealing process. It is soft, tough and easily machined metal

D. contains 1.7 to 3.5% carbon in free state and is obtained by the slow cooling of molten cast iron

E. 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

1673. The percentage of carbon in pig iron varies from___________________?
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A. 4.5 to 6.3%.

B. 4 to 4.5%

C. 1.5 to 2.5%

D. 0.1 to 1.2%

E. 2.5 to 4%

1674. The crystal structure of gamma iron is_________________?
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A. body centred cubic

B. orthorhombic crystal

C. hexagonal close packed

D. face centred cubic

E. cubic structure