Mechanical Engineering Mcqs

The air entry velocity m a rocket as compared to aircraft is_________________?

(A) same

(B) more

(C) less

(D) zero

(D) dependent on power and speed

Submitted By: Ali Uppal


Submitted By: Ali Uppal


The maximum propulsion efficiency of a turbojet is attained at around following speed __________________?

(A) 550 km/hr

(B) 1050km/hr

(C) 1700 km/hr

(D) 2400km /hr

(D) 4000 km/hr

Submitted By: Ali Uppal


A rocket works with maximum overall efficiency when air craft velocity is equal to the_________________?

(A) jet velocity

(B) twice the jet velocity

(C) half the jet velocity

(D) average of the jet velocity

(D) no such co-relationship with jet velocity exists

Submitted By: Ali Uppal


In the cross compounding of the gas turbine plant__________________?

(A) h.p. compressor L connected to h.p. turbine and l.p. compressor ot l.p. tur-bine

(B) h.p. compressor is connected to l.p. turbine and l.p. compressor is con-nected to h.p. turbine

(C) both the arrangements can be employed

(D) all are connected in series

(D) none of the above

Submitted By: Ali Uppal


Work ratio of a gas turbine plant is ratio of______________________?

(A) net work output and work done by turbine

(B) net work output and heat supplied

(C) work done by turbine and heat supplied

(D) work done by turbine and net work output

(D) actual/heat drop and isentropic heat drop

Submitted By: Ali Uppal


In the aircraft propellers __________________?

(A) the propulsive matter is caused to flow around the propelled body

(B) propulsive matter is ejected from within the propelled body

(C) its functioning does not depend on presence of air

(D) all of the above

(D) none of the above

Submitted By: Ali Uppal


Work ratio of a gas turbine may be improved by f____________________?

(A) decreasing the compression work

(B) increasing the compression work

(C) increasing the turbine work

(D) decreasing the turbine work

Submitted By: Ali Uppal


Reheating in gas turbine results in___________________?

(A) increase of work ratio

(B) decrease of thermal efficiency

(C) decrease of work ratio

(D) both

Submitted By: Ali Uppal


In which case the air-fuel ratio is likely to be maximum _________________?

(A) 2-stroke engine

(B) 4-stroke petrol engine

(C) 4-stroke diesef engine

(D) multi-cylinder engine

(D) gas turbine

Submitted By: Ali Uppal