Q.1.
Thermodynamic processes are indicated in the following diagram. Match the following
| Column-1 | Column-2 |
| P. Process I | a. Adiabatic |
| Q. Process II | b. Isobaric |
| R. Process III | c. Isochoric |
| S. Process IV | d. Isothermal |
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43%
a) a) P → a, Q → c, R → d, S → b
-
29%
b) P → c, Q → a, R → d, S → b
-
0%
c) P → c, Q → d, R → b, S → a
-
29%
d) P → d, Q → b, R → a, S → c
Q.2.
A Carnot engine having an efficiency of 1/10 as heat engine, is used as a refrigerator. If the work done onthe system is 10 J, the amount of energy absorbed from the reservoir at lower temperature is … [ NEET 2017]
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14%
a) 1 J
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0%
b) 90 J
-
43%
c) 99 J
-
43%
d) 100 J
Explanation
Q.3.
The given below p-v diagram represents the thermodynamic cycleof an engine, operating with an ideal monoatomic gas. Theamount of heat, extracted from the source in a single cycle is … [ IIT Mains 2013]
-
33%
a) P0V0
-
17%
b)
-
33%
c)
-
17%
d) 4P0V0
Explanation
Q.4.
Two non-reactive monoatomic ideal gases have their atomic masses in the ratio 2 :The ratio of their partial pressures, when enclosed in a vessel kept at a constant temperature, is 4 :The ratio of their densities is
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33%
a) 1 : 4
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0%
b) 1 : 2
-
67%
c) 6 : 9
-
0%
d) 8 : 9
Explanation
Q.5.
Paragraph One mole of a monatomic ideal gas is taken along two cyclic processes E → F → G → E and E → F → H → E as shown in the PV diagram. The processes involved are purely isochoric, isobaric, isothermal or adiabatic. Match the paths in List I with the magnitudes of the work done in List II and select the correct answer using the codes given below the lists.
| List I | List II |
| P. G → E | 160 P0V0 1n2 |
| Q. G → H | 36 P0V0 |
| R. F → H | 24 P0V0 |
| S. F → G | 31 P0V0 |
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33%
a) P → 4, Q → 3, R → 2, S → 1
-
0%
b) P → 4 , Q → 3, R → 1, S → 2
-
17%
c) P → 3, Q → 1, R → 2 S → 4
-
50%
d) P → 1, Q → 3 , R → 2 , S → 4
Explanation
Q.6.
PARAGRAPH In the figure a container is shown to have a movable (without friction)piston on top. The container and the piston are all made of perfectlyinsulating material allowing no heat transfer between outside and inside thecontainer. The container is divided into two compartments by a rigidpartition made of a thermally conducting material that allows slow transferof heat. The lower compartment of the container is filled with 2 moles of an ideal monatomic gas at 700 K and the upper compartment is filled with 2moles of an ideal diatomic gas at 400 K. The heat capacities per mole of an ideal monatomic gas are Cv=3R/2 , Cp= 5R/2 and thosefor an ideal diatomic gas are CvM = 5R/2 , Cp=7R/2 . 187A) Consider the partition to be rigidly fixed so that it does not move. When equilibrium isachieved, the final temperature of the gases will be
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0%
a) 550 K
-
0%
b) 525 K
-
67%
c) 513 K
-
33%
d) 490 K
Explanation
Q.7.
than one correct answer Q188) A container of fixed volume has a mixture of one mole of hydrogen and one mole of heliumin equilibrium at temperature T. Assuming the gases are ideal, the correct statement(s)is(are)
-
20%
a) The average energy per mole of the gas mixture is 2RT
-
20%
b) The ratio of speed of sound in the gas mixture to that in helium gas is √(6/5)
-
20%
c) The ratio of the rms speed of helium atoms to that of hydrogen molecules is 1/2
-
40%
d) The ratio of the rms speed of helium atoms to that of hydrogen molecules is 1/√2
Explanation
Q.8.
An ideal monoatomic gas is confined in a horizontal cylinder by a spring loaded piston (as shown in the figure). Initially the gas is at temperature T1, pressure P1 and volume V1 and the spring is in its relaxed state. The gas is then heated very slowly to temperature T2, pressure P2 and volume VDuring this process the piston moves out by a distance x. Ignoring the friction between the piston and the cylinder, the correct statement(s) is(are) ... [IIT Advance 2015]
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50%
a) If V2 = 2V1 and T2 = 3T1, then the energy stored in the spring is P1 V1/4
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0%
b) If V2 = 2V1 and T2 = 3T1, then the change in internal energy is 3P1V1
-
25%
c) If V2 = 3V1 and T2 = 4T1, then the work done by the gas is 7P1V1/3
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25%
d) If V2 = 3V1 and T2 = 4T1, then the heat supplied to the gas is 17 P1V1/6
Explanation
Q.9.
One mole of an ideal gas at 300 K in thermal contact with surroundings expands isothermally from 1.0 L to 2.0 L against a constant pressure of 3.0 atm. In this process, the change in entropy of surroundings (ΔSsurr) in JK-1 is (1 L atm = 101.3 J) [IIT Advance 2016]
-
0%
a) 5.763
-
25%
b) 1.013
-
75%
c) -1.013
-
0%
d) -5.763
Explanation
Q.10.
A gas is enclosed in a cylinder with a movable frictionless piston. Its initial thermodynamic state at pressure Pi = 105 Pa and volume Vi = 10-3 m3 changes to a final state at Pf = (1/32) × 105 Pa and Vf = 8 × 10-3 m3 in an adiabatic quasi-static process, such that P3V5 = constant. Consider another thermodynamic process that brings the system from the same initial state to the same final state in two steps: an isobaric expansion at Pi followed by an isochoric (isovolumetric) process at volume Vf. The amount of heat supplied to the system in the two-step process is approximately … [ IIT Advance 2016]
-
0%
a) 112 J
-
50%
b) 294 J
-
25%
c) 588 J
-
25%
d) 813 J
Explanation
Q.11.
PARAGRAPH Answer 192A, 192B and 192C by appropriately matching the information given in the three columns of the following table. An ideal gas is undergoing a cyclic thermodynamics process in different ways as shown in the corresponding P–V diagrams in column 3 of the table. Consider only the path from state 1 to stateW denotes the corresponding work done on the system. The equations and plots in the table have standard notations as used in thermodynamics processes. Here γ is the ratio of heat capacities at constant pressure and constant volume. The number of moles in the gas is n. Q192A) Which of the following options is the only correct representation of a process in which ΔU = ΔQ – PΔV?
| Column-1 | Column-2 | Column-3 |
 | (i) Isothermal |  |
 | (ii) Isochoric |  |
 | (iii) Isobaric |  |
| (iv) Adiabatic |  |
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50%
a) (II) (iv) (R)
-
0%
b) (II) (iii) (P)
-
0%
c) (II) (iii) (S)
-
50%
d) (III) (iii) (P)
Explanation
