11) Work done is zero for the following process
a) constant volume
b) free expansion
c) throttling
d) all of the above
12) In free expansion process
a) W1-2 =0
b) Q1-2 = 0
c) du = 0
d) All of the above
13) Internal energy is defined by
a) Zeroth law of thermodynamics
b) first law of thermodynamics
c) Second law of thermodynamics
d) Law of entropy
14) The first law of thermodynamics is the law of
a) conservation of mass
b) conservation of energy
c) conservation of momentum
d) conservation of temperature
15) Compressed air coming out from a punctured football
a) becomes hotter
b) becomes cooler
c) remains at same temperature
d) attains atmospheric temperature
16)Second law of thermodynamics defines
a) Heat
b) Work
c) Enthalpy
d) Entropy
17) Kelvin-plank law deals with
a) conservation of energy
b) conservation of heat
c) conservation of mass
d) conservation of heat into work
18) If a heat engine gives an output of 3 kW when the input is 10000J/sec then the thermal efficiency of the engine will be
a) 20%
b) 30%
c) 70%
d) 76.7%
19) When a system is in equilibrium, any conceivable change in entropy would be
a) maximum
b) zero
c) positive
d) negative
20) The value of entropy at 0k is taken as
a) 1
b) 0
c) -1
d) any value