Mechanical Engineering Mcqs

Diesel fuel, compared to petrol is_________________?

(A) less difficult to ignite

(B) just about the same difficult to ignite

(C) more difficult to ignite

(D) highly ignitable

(D) none of the above

Submitted By: Ali Uppal


The air-fuel ratio of the petrol engine is controlled by__________________?

(A) fuel pump

(B) governor

(C) injector

(D) carburettor

(D) scavenging

Submitted By: Ali Uppal


The accunmulation of carbon in a cylinder results in increase of________________?

(A) clearance volume

(B) volumetric efficiency

(C) ignition time

(D) effective compression ratio

(D) valve travel time.

Submitted By: Ali Uppal


The precess of breaking up or a lipuid into fine droplets by spraying is called___________________?

(A) vaporisation

(B) carburetion

(C) ionisation

(D) injection

(D) atomisation

Submitted By: Ali Uppal


In a typical medium speed 4-stroke cycle diesel engine________________?

(A) compression starts at 35° after bottom dead center and ends at top dead center

(B) compression starts at bottom dead center and ends at top dead center

(C) compression starts at 10° before bottom dead center and, ends just before top dead center

(D) may start and end anywhere

(D) none of the above

Submitted By: Ali Uppal


The mean effective pressure obtained from engine indicator indicates the________________?

(A) maximum pressure developed

(B) minimum pressure

(C) instantaneous pressure at any instant

(D) exhaust pressure

(D) average pressure

Submitted By: Ali Uppal


In a typical medium speed 4 stroke cycle diesel engine_______________?

(A) exhaust valve opens at 35° before bot-tom dead center and closes at 20° after top dead center

(B) exhaust valve opens at bottom ‘dead center and closes at top dead center

(C) exhaust valve opens just after bottom dead center and closes just before top dead center

(D) may open and close anywhere

(D) none of the above is true

Submitted By: Ali Uppal


Supercharging is essential in_____________?

(A) diesel engines

(B) gas turbines

(C) petrol engines

(D) aircraft engines

(D) marine engines

Submitted By: Ali Uppal


The reason for supercharging in any engine is to________________?

(A) increase efficiency

(B) increase power

(C) reduce weight and bulk for a given out-put

(D) effect fuel economy

(D) none of the above

Submitted By: Ali Uppal


The actual volume of fresh charge admitted in 4-stroke petrol engine is_________________?

(A) equal to stroke volume

(B) equal to stroke volume and clearance volume

(C) less than stroke volume

(D) more than stroke volume

(D) more than cylinder volume

Submitted By: Ali Uppal