Study & Learn

Mechanical Engineering MCQs with Explanations

Read every question, see the correct answer, and understand the explanation at your own pace. Study mode has no timer and no negative marking.

21%

450 of 2,110MCQs reviewed

Study Mode — explanations are always visiblePrefer a timed quiz? Start test

451Mechanical EngineeringMedium

Injection lag is________?

Athe time taken by fuel after injection (before top dead center) to reach upto auto-ignition temperature

Btime corresponding to actual injection and top dead center

Cnone of the above

Dtime before actual fuel injection and the pump pluger starts to pump fuel

Etime corresponding to actual ignition and top dead center

Correct answer

D. time before actual fuel injection and the pump pluger starts to pump fuel

Explanation

The correct answer is time before actual fuel injection and the pump pluger starts to pump fuel.

452Mechanical EngineeringMedium

The elastic stress strain behaviour of rubber is________?

Alinear

Bplastic

Cnon-linear

Dno fixed relationship

Eunpredictable behaviour

Correct answer

C. non-linear

Explanation

The correct answer is non-linear.

453Mechanical EngineeringMedium

If a pump is handling water and is discharging a certain flow Q at a constant total dynamic head requiring a definite B.H.P., the same pump when handling a liquid of specific gravity 0.75 and viscosity nearly same as of water would discharge________?

AQ/0.75

Bsame quantity of liquid

Cnone of the above

D1.5 Q

E0.75 Q

Correct answer

B. same quantity of liquid

Explanation

The correct answer is same quantity of liquid.

454Mechanical EngineeringMedium

Resultant pressure of the liquid in the case of an immersed body acts through________?

Acentre of gravity

Bmetacentre

Ccentre of pressure

Din between e.g. and centre of pressure

Ecentre of buoyancy

Correct answer

C. centre of pressure

Explanation

The correct answer is centre of pressure.

455Mechanical EngineeringMedium

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________?

Anone of the above

B2pa2R2

Cpco2/?2/2

Dpco2/?2

Epa2R/2

Correct answer

C. pco2/?2/2

Explanation

The correct answer is pco2/?2/2.

456Mechanical EngineeringMedium

Coaxing is the procedure of increasing________?

Ametal strength by cycling

Bmetal hardness by surface treatment

Cnone of the above

Dmetal resistance to corrosion by coating

Efatigue limit by overstressing the metal by successively increasing loadings

Correct answer

E. fatigue limit by overstressing the metal by successively increasing loadings

Explanation

The correct answer is fatigue limit by overstressing the metal by successively increasing loadings.

457Mechanical EngineeringMedium

The appellate authority for an industrial dispute is________?

Ahigh court/supreme court

Blabour court

Cboard of directors

Dpresident

Emanagement

Correct answer

A. high court/supreme court

Explanation

The correct answer is high court/supreme court.

458Mechanical EngineeringMedium

A cylindrical section having no joint is known as ________?

Aseamless section

Bhomogeneous section

Cmanufactured section

Dperfect section

Ejointless section

Correct answer

A. seamless section

Explanation

The correct answer is seamless section.

459Mechanical EngineeringMedium

Steady flow occurs when________?

Athe magnitude and direction of the velocity do not change from point to point in the fluid

Bthe fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each plane

Cthe velocity of successive fluid particles, at any point, is the same at successive periods of time

Dvelocity, depth, pressure, etc. change from point to point in the fluid flow

Ethe direction and magnitude of the velocity at all points are identical

Correct answer

C. the velocity of successive fluid particles, at any point, is the same at successive periods of time

Explanation

The correct answer is the velocity of successive fluid particles, at any point, is the same at successive periods of time.

460Mechanical EngineeringMedium

If a fluid expands suddenly into vacuum through an orifice of large dimension, then such a process is called________?

Aadiabatic expansion

Bfree expansion

Chyperbolic expansion

Dthrottling

Eparabolic expansion

Correct answer

B. free expansion

Explanation

The correct answer is free expansion.

Injection lag is________?

Athe time taken by fuel after injection (before top dead center) to reach upto auto-ignition temperature

Btime corresponding to actual injection and top dead center

Cnone of the above

Dtime before actual fuel injection and the pump pluger starts to pump fuel

Etime corresponding to actual ignition and top dead center

Correct answer

D. time before actual fuel injection and the pump pluger starts to pump fuel

Explanation

The correct answer is time before actual fuel injection and the pump pluger starts to pump fuel.

Coaxing is the procedure of increasing________?

Ametal strength by cycling

Bmetal hardness by surface treatment

Cnone of the above

Dmetal resistance to corrosion by coating

Efatigue limit by overstressing the metal by successively increasing loadings

Correct answer

E. fatigue limit by overstressing the metal by successively increasing loadings

Explanation

The correct answer is fatigue limit by overstressing the metal by successively increasing loadings.

Steady flow occurs when________?

Athe magnitude and direction of the velocity do not change from point to point in the fluid

Bthe fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each plane

Cthe velocity of successive fluid particles, at any point, is the same at successive periods of time

Dvelocity, depth, pressure, etc. change from point to point in the fluid flow

Ethe direction and magnitude of the velocity at all points are identical

Correct answer

C. the velocity of successive fluid particles, at any point, is the same at successive periods of time

Explanation

The correct answer is the velocity of successive fluid particles, at any point, is the same at successive periods of time.