A diatomic ideal gas is used in a Carnot engine as the working substance. If during the adiabatic expansion part of the cycle the volume of the gas increased from V to 32 V, the efficiency of the engine is
0.25
0.5
0.75
0.99
Universal gas constant is
CP - CV
CP + CV
A thermodynamic system is taken through the cycle PQRSP process. The net work done by the system is
20 J
-20 J
400 J
-374 J
In an adiabatic system which is true ?
PγTγ-1 = constant
PγT1-γ = constant
PTγ = constant
P1-γTγ = constant
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
The efficiency of Carnot engine is 50% and temperature of sink is 500 K. If the temperature of source is kept constant and its efficiency is to be raised to 60%, then the required temperature of the sink will be
600 K
500 K
400 K
100 K
"Heat cannot itself flow from a body at lower temperature to a body at higher temperature" is a statement or consequence of
second law of thermodynamics
conservation of momentum
conservation of mass
first law of thermodynamics
The volume (V) versus temperature (T) graphs for a certain amount of a perfect gas at two pressures P1 and P2are shown in the figure. It follows from the graph that
P1 > P2
P1 < P2
P1 = P2
information is insufficient to draw any conclusion.
5.6 litre of helium gas at STP is adiabatically compressed to 0.7 litre. Taking the initial temperature to be T1, the work done in the process is
An ideal gas heat engine is operating between 227oC and 127oC. It absorbs 104 J of heat at the higher temperature. The amount of heat converted into work is
2000 J
4000 J
8000 J
5600 J
