435. What are the limitations to the signs of heat exchange from hot and cold reservoirs if a two-temperature machine operates between two negative temperatures
A.Heat must be rejected to hot source and abstracted from cold source
B.No limitation
C.Heat must be rejected to both the sources
D.Heat must be abstracted from both the sources
436. An ideal gas at 27°C is heated at constant pressure till its volume becomes three times. The temperature of gas then will be
A.81°C
B.900°C
C.627°C
D.927°C
437. According to Pettlier Thomson effect
A.It is impossible to construct a heat engine which operates in a cycle and receives a given amount of heat from a high temperature body and does equal amount of work
B.It is impossible to construct a device which operates in a cycle and produces no effect other than the transfer of heat from a cooler body to hotter body
C.When two dissimilar metals are heated at one end and cooled at other, e.m.f. is developed proportional to difference of temperatures at two ends
D.Heat can be converted into work
438. All diesel cycles except slow speed engines use following cycle
A.Diesel
B.Otto
C.Joule
D.Mixed dual
439. Second law of thermodynamics defines
A.Entropy
B.Enthalpy
C.Heat
D.Work
440. Gas turbines work on
A.Constant pressure cycle
B.Constant volume cycle
C.Constant temperature cycle
D.Constant enthalpy cycle
441. Cycle used in thermal power plants is
A.Carnot
B.Reversed Carnot
C.Rankine
D.Brayton
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