Mechanical Engineering Mcqs

The clearance volume of the air compressor is kept minimum because____________________?

(A) it allows maximum compression to be achieved

(B) it greatly affects volumetric efficiency

(C) it results in minimum work

(D) it permits isothermal compression

(D) none of the above

Submitted By: Ali Uppal


Ratio of indicated h.p. to shaft h.p. in known as__________________?

(A) compressor efficiency

(B) isothermal efficiency

(C) volumetric efficiency

(D) mechanical efficiency

(D) adiabatic efficiency

Submitted By: Ali Uppal


Euler’s equation is applicable for__________________?

(A) centrifugal compressor

(B) axial compressor

(C) pumps

(D) all of the above

(D) none of the above

Submitted By: Ali Uppal


Which is false statement about multistage compression ?

(A) Power consumption per unit of air delivered is low

(B) Volumetric efficiency is high

(C) It is best suited for compression ratios around 7:1

(D) The moisture in air is condensed in the intercooler

(D) Outlet temperature is reduced

Submitted By: Ali Uppal


Out of the following, from where you will prefer to take intake for air compressor_________________?

(A) from an air conditioned room maintained at 20°C

(B) from outside atmosphere at 1°C

(C) from coal yard side

(D) from a side where cooling tower is located nearby

(D) from any one of the above locations

Submitted By: Ali Uppal


Volumetric efficiency of a compressor with clearance volume ________________?

(A) increases with increase in compression ratio

(B) decreases with increase in compression ratio

(C) in not dependent upon compression ratio

(D) may increase/decrease depending on compressor capacity

(D) unpredictable

Submitted By: Ali Uppal


Clearance volume in actual reciprocating compressors is essential __________________?

(A) to accommedate Valves in the cylinder head

(B) to provide cushioning effect

(C) to attain high volumetric efficiency

(D) to avoid mechanical bang of piston with cylinder head

(D) to provide cushioning effect and also to avoid mechanical bang of piston with cylinder head

Submitted By: Ali Uppal


The net work input required for compressor with increase in clearance volume_____________________?

(A) increases

(B) decreases

(C) remains same

(D) increases/decreases depending on com-pressor capacity

(D) unpredictable

Submitted By: Ali Uppal


The ratio of work doen per cycle to the swept volume in case of compressor is called ______________?

(A) compression index

(B) compression ratio

(C) compressor efficiency

(D) mean effective pressure

(D) compressor effectiveness

Submitted By: Ali Uppal


The compressor performance at higher altitude compared to sea level will be _______________?

(A) same

(B) higher

(C) lower

(D) dependent on other factors

(D) none of the above

Submitted By: Ali Uppal