Mechanical Engineering Mcqs

The C.O.P. of a refrigeration cycle with lowering of condenser temperature, keeping the evaporator temperature constant, will__________________?

(A) increase

(B) decrease

(C) may increase or decrease depending on the type of refrigerant used

(D) remain unaffected

(D) unpredictable

Submitted By: Ali Uppal


The evolution of heat of solution takes place in ammonia absorption plant when _____________________?

(A) ammonia vapour goes into solution

(B) ammonia vapour is driven out of solution

(C) lithium bromide mixes with ammonia

(D) weak solution mixes with strong solution

(D) lithium bromide is driven out of solution

Submitted By: Ali Uppal


The COP of a vapor compression plant in comparison to vapor absorption plant is ________________?

(A) more

(B) less

(C) same

(D) more/less depending on size of plant

(D) unpredictable

Submitted By: Ali Uppal


Submitted By: Ali Uppal


Which of the following refrigerants has lowest freezing point_______________?

(A) Freon-12

(B) NH3

(C) C02

(D) Freon-22

(D) S02

Submitted By: Ali Uppal


The refrigeration effect in a dry evaporator compared to flooded evaporator in a similar plant is_________________?

(A) same

(B) more

(C) less

(D) more or less depending on ambient conditions

(D) unpredictable

Submitted By: Ali Uppal


Reducing suction pressure in refrigeration cycle_________________?

(A) lowers evaporation temperature

(B) increases power required per ton of refrigeration

(C) lowers compressor capacity because vapour is lighter

(D) reduces weight displaced by piston

(D) all of the above

Submitted By: Ali Uppal


Most of the domestic refrigerators work on the following refrigeration system _________________?

(A) vapour compression

(B) vapour absorption

(C) carnot cycle

(D) electrolux refrigerator

(D) dual cycle

Submitted By: Ali Uppal


Submitted By: Ali Uppal


Ammonia is __________________?

(A) non-toxic

(B) non-inflammable

(C) toxic and non-inflammable

(D) highly toxic and inflammable

(D) none of the above

Submitted By: Ali Uppal