ISRO SC/ENG 2013

 1) The definition of 1 K as per the internationally accepted temperature scale is

A. 1/100 th the difference between normal boiling point and normal freezing point of water
B. 1/273.15 th the normal freezing point of water
C. 100 times the difference between the triple point of water and the normal freezing point of water
D. 1/273.16 th of the triple point of water

 2) A system undergoes a state change from 1 to 2. According the second law of thermodynamics for the process to be feasible, the entropy change, S2 – S1 of the system

A. Is positive or zero
B. is negative or zero
C. Is zero
D. can be, positive, negative or zero

 3) A positive value of Joule-Thomson coefficient of a fluid means

A. Temperature drops during throttling
B. Temperature remains constant during throttling
C. Temperature rises during throttling
D. None of these

 4) A carnot engine rejects 30% of absorbed heat to a sink at 30 0 C. the temperature of the heat source is

A. 100 C
B. 433 C
C. 737 C
D. 1010 C

 5) An engine operates between temperature limits of 900 K and T and T and 400 K. for both to be equally efficient, the values of T will be

A. 700 K
B. 600 K
C. 750 K
D. 650 K