Mechanical Engineering Mcqs

More than one stage will be preferred for reciprocating compressor if the delivery pressure is more than____________________?

(A) 2 kg/cm2

(B) 6 kg/cm2

(C) 10 kg/cm2

(D) 14.7 kg/cm2

(D) none of the above

Submitted By: Ali Uppal


Pick up the wrong statement about advantages of multistage compression____________________?

(A) better lubrication is possible advantages of multistage

(B) more loss of air due to leakage past the cylinder

(C) mechanical balance is better

(D) air can be cooled perfectly in between

(D) more uniform torque, light cylinder and saving in work

Submitted By: Ali Uppal


Losses in a centrifugal compressor are due to__________________?

(A) inlet losses

(B) impeller channel losses

(C) diffuser losses

(D) all of the above

(D) none of the above

Submitted By: Ali Uppal


Submitted By: Ali Uppal


The criterion of the thermodynamic efficiency for rotary compressor is_________________?

(A) isentropic compression

(B) isothermal compression

(C) polytropic compression

(D) any one of the above

(D) none of the above

Submitted By: Ali Uppal


Submitted By: Ali Uppal


For minimum work in multistage compression, assuming same index of compression in all stages_________________?

(A) work done in first stage should be more

(B) work done in subsequent stages should increase

(C) work done in subsequent stages should decrease

(D) work done in all stages should be equal

(D) work done in any stage is no criterion for minimum work but depends on other factors

Submitted By: Ali Uppal


Which is false statement about advantages of multistage compressor in comparison to single stage compressor_________________?

(A) less power requirement

(B) better mechanical balance

(C) less loss of air due to leakage past the cylinder

(D) more effective lubrication

(D) lower volumetric efficiency

Submitted By: Ali Uppal


The work ratio of simple gas turbine cycle depends on_________________?

(A) pressure ratio

(B) maximum cycle temperature

(C) minimum cycle temperature

(D) all of the above

(D) none of die above

Submitted By: Ali Uppal


The vloumetric efficiency of compressor with increase in compression ratio will ___________________?

(A) increase

(B) decrease

(C) remain same

(D) may increase/decrease depending on clearance volume

(D) none of the above

Submitted By: Ali Uppal