P-V diagram of a diatomic gas is a straight line passing through origin. The molar heat capacity of the gas in the process will be -
1. 4 R
2. 2.5 R
3. 3 R
4.
Following figure shows on adiabatic cylindrical container of volume V0 divided by an adiabatic smooth piston (area of cross-section = A) in two equal parts. An ideal gas is at pressure P1 and temperature T1 in left part and gas at pressure P2 and temperature T2 in right part. The piston is slowly displaced and released at a position where it can stay in equilibrium. The final pressure of the two parts will be (Suppose x = displacement of the piston)
(1) P2
(2) P1
(3)
(4)
Two cylinders A and B fitted with pistons contain equal amounts of an ideal diatomic gas at 300 K. The piston of A is free to move while that of B is held fixed. The same amount of heat is given to the gas in each cylinder. If the rise in temperature of the gas in A is 30 K, then the rise in temperature of the gas in B is
(1) 30 K
(2) 18 K
(3) 50 K
(4) 42 K
A system goes from A to B via two processes I and II as shown in figure. If ΔUI and ΔUII are the changes in internal energies in the processes I and II respectively, then
(1) ΔUII > ΔUI
(2) ΔUII < ΔUI
(3) ΔUI = ΔUII
(4) Relation between ΔUI and ΔUII can not be determined
A thermodynamic system is taken through the cycle PQRSP process. The net work done by the system is -
(1) 20 J
(2) – 20 J
(3) 400 J
(4) – 374 J
The P-V diagram shows seven curved paths (connected by vertical paths) that can be followed by a gas. Which two of them should be parts of a closed cycle if the net work done by the gas is to be at its maximum value
(1) ac
(2) cg
(3) af
(4) cd
An ideal gas of mass m in a state A goes to another state B via three different processes as shown in figure. If Q1, Q2 and Q3 denote the heat absorbed by the gas along the three paths, then -
(1) Q1 < Q2 < Q3
(2) Q1 < Q2 = Q3
(3) Q1 = Q2 > Q3
(4) Q1 > Q2 > Q3
Which of the following graphs correctly represents the variation of with P for an ideal gas at constant temperature ?
(1)
(2)
(3)
(4)
A thermodynamic process is shown in the figure. The pressures and volumes corresponding to some points in the figure are : and . 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
(1) 560 J
(2) 800 J
(3) 600 J
(4) 640 J
P-V plots for two gases during adiabatic process are shown in the figure. Plots 1 and 2 should correspond respectively to -
(1) He and O2
(2) O2 and He
(3) He and Ar
(4) O2 and N2