Which one of the following is not a state function ?
temperature
entropy
pressure
work
A scientist says that the efficiency of his heat engine which works at source temperature of 127oC and sink temperature 27oC is 26%.
It is impossible
It is possible but less probable
It is quite possible
Data is incomplete
A thermodynamic process is shown in the figure. The pressure and volumes corresponding to some points in the figure are
PA = 3 × 104 Pa, VA = 2 × 10-3 m3
PB = 8 × 104 Pa, VB = 5 × 10-3 m3
In process AB, 600 J of heat is added to the system and in process BC, 200 J of heat is added to the system. The change in internal energy of the system in process AC would be
560 J
800 J
600 J
640 J
The efficiency of a Carnot engine operating between temperatures of 100oC and -23oC will be
The number of translational degree of freedom for a diatomic gas is
2
3
5
6
We consider a thermodynamic system. If ΔU represents the increase in its internal energy and W the work done by the system, which of the following statements is true?
ΔU = - W in an adiabatic process
ΔU = W in an isothermal process
ΔU = - W in an isothermal process
ΔU = W in an adiabatic process
An ideal gas is compressed adiabatically to 8/27 times of its present value at 27oC. The temperature of the gas becomes (γ= 5/3).
475oC
275oC
402oC
175oC
Even Carnot engine cannot give 100% efficiency, because we cannot
prevent radiation
find ideal sources
reach absolute zero temperature
eliminate friction
An ideal mono atomic gas is taken around the cycle ABCDA as shown in the PV diagram. The work done during the cycle is given by
1/2 PV
PV
2 PV
4 PV
In an adiabatic process, the state of a gas is changed from P1, V1, T1 to P2, V2, T2. Which of the following relations is correct ?
