mechanical engineering MCQs – Page 135

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 Review each marked answer and report any item that may be outdated or unclear.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

2681. Tungsten in steel________________?
0

A. improves wear resistance, cutting ability and toughness

B. refines grain size and produces less tendency to carburisation, improves corrosion and heat resistant properties

C. improves cutting ability and reduces hardenability

D. gives ductility, toughness, tensile strength and anticorrosion properties

E. raises its melting point

2682. White cast iron__________________?
0

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

B. none of the above

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

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

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

2683. The transistor is made of___________________?
0

A. germanium

B. german silver

C. copper

D. silver

E. gold

2684. Tungsten in high speed steel provides________________?
0

A. cold hardness

B. toughness

C. wear resistance

D. hot hardness

E. sharp cutting edge

2685. The tensile strength of wrought iron is maximum _________________?
0

A. along the lines of slag distribution

B. uniform in all directions

C. none of the above

D. perpendicular to lines of slag distribution

E. unpredictable

2686. Austenite rs a combination of_________________?
0

A. ferrite and iron graphite

B. pearlite and ferrite

C. ferrite and austenite

D. ferrite and cementite

E. cementite and gamma iron

2687. Admiralty brass used for steam condenser tubes contains copper and zinc in the following ratio_________________?
0

A. 60:40:00

B. 30 : 70

C. 50:50:00

D. 40 : 60

E. 70:30:00

2688. Nodular iron has____________________?
0

A. all of the above

B. high maehinability

C. low melting point

D. good fluidity

E. high tensile strength

2689. Structural steel contains following principal alloying elements__________________?
0

A. zinc, sulphur, and chromium

B. nickel, chromium and manganese

C. none of the above

D. tungsten, molybdenum and phosphorous

E. lead, tin, aluminium

2690. Free cutting steels_____________________?
0

A. contain carbon in free form

B. require least cutting force

C. are used where ease in machining is the criterion

D. can be cut freely even under adverse conditions

E. do not exist

2691. Which is false statement about annealing. Annealing is done to________________?
0

A. harden steel slightly

B. permit further cold working

C. soften material

D. relieve stresses

E. improve machining characteristic

2692. The usual composition of a soldering alloy is__________________?
0

A. tin and lead

B. tin, lead and silver

C. tin, copper and lead

D. tin, lead and small percentage of antimony

E. tin and copper

2693. Gun metal contains__________________?
0

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

B. 85-92% copper and rest zinc

C. 90% copper and 10% tin

D. 70-78% copper and rest tin

E. 70% copper and 30% zinc

2694. A specimen of aluminium metal when observed under microscope shows __________________?
0

A. a complex cubic structure

B. F.C.C. crystal structure

C. B.C.C. crystalline structure

D. H.C.P. structure

E. orthorhombic crystalline structure

2695. Pig iron is the name given to________________?
0

A. product of blast furnace made by reduction of iron ore

B. iron scrap

C. raw material for blast furnace

D. iron in molten form in the ladles

E. iron containing huge quantities of carbon

2696. Grey cast iron_____________________?
0

A. is also known as chilled cast iron am is obtained by cooling rapidly. It i: almost unmachinable

B. is produced by small additions o magnesium (or cerium) in the ladle Graphite is in nodular or spheroida form and is well dispersed throughout the material

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

D. is produced by annealing process. I is soft, tough and easily machinec metal

E. none of the above is true

2697. Brass contains___________________?
0

A. 70-75% copper and rest tin

B. 90% copper and 10% tin

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

D. 70% copper and 30% zinc

E. 70% copper and 30% tin

2698. Basic constituents of Monel metal are _________________?
0

A. zinc, tin, lead

B. nickel, lead and tin