Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Heat and Thermodynamics

83 questions · Physics · NEET
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /NEET
  3. /Physics
  4. /Heat and Thermodynamics

Heat and Thermodynamics

83 questions · Physics · NEET

  1. Three identical heat conducting rods are connected in series as shown in the figure. The rods on the sides have thermal conductivity 2K while that in the middle has thermal conductivity K. The left end of the combination is maintained… Includes diagram2025 · Q142 · MCQ
  2. A container has two chambers of volumes V1​=2 litres and V2​=3 litres separated by a partition made of a thermal insulator. The chambers contain n1​=5 and n2​=4 moles of ideal gas at pressures p1​=1 atm and p2​=2 atm…2025 · Q154 · MCQ
  3. An oxygen cylinder of volume 30 litre has 18.20 moles of oxygen. After some oxygen is withdrawn from the cylinder, its gauge pressure drops to 11 atmospheric pressures at temperature 27∘C. The mass of the oxygen…2025 · Q161 · MCQ
  4. Two gases A and B are filled at the same pressure in separate cylinders with movable pistons of radius rA​ and rB​, respectively. On supplying an equal amount of heat to both the systems reversibly under constant pressure, the…2025 · Q163 · MCQ
  5. A thermodynamic system is taken through the cycle abcda. The work done by the gas along the path bc is: Includes diagram2024 · Q164 · MCQ
  6. The following graph represents the T-V curves of an ideal gas (where T is the temperature and V the volume) at three pressures P1​,P2​ and P3​ compared with those of Charles's law represented as dotted lines. Then the correct… Includes diagram2024 · Q190 · MCQ
  7. Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R. Assertion A: Houses made of concrete roofs overlaid with foam keep the room hotter during summer. Reason R: The…2024 · Q173 · MCQ
  8. The equilibrium state of a thermodynamic system is described by A. Pressure B. Total heat C. Temperature D. Volume E. Work done Choose the most appropriate answer from the options given below.2024 · Q183 · MCQ
  9. According to the law of equipartition of energy, the number of vibrational modes of a polyatomic gas of constant γ=Cv​Cp​​ is (CP​ where CV​ are the specific heat capacities of the gas at constant pressure and constant…2024 · Q197 · MCQ
  10. For the given cycle, the work done during isobaric process is: Includes diagram2023 · Q135 · MCQ
  11. A container of volume 200 cm3 contains 0.2 mole of hydrogen gas and 0.3 mole of argon gas. The pressure of the system at temperature 200 K (R=8.3JK−1 mol−1) will be :-2023 · Q165 · MCQ
  12. The temperature of a gas is −50∘C. To what temperature the gas should be heated so that the rms speed is increased by 3 times?2023 · Q127 · MCQ
  13. A Carnot engine has an efficiency of 50% when its source is at a temperature 327∘C. The temperature of the sink is :-2023 · Q129 · MCQ
  14. An ideal gas follows a process described by the equation PV2=C from the initial (P1​,V1​,T1​) to final (P2​,V2​,T2​) thermodynamic states, where C is a constant. Then2022 · Q152 · MCQ
  15. Two rods one made of copper and other made of steel of same length and same cross sectional area are joined together. The thermal conductivity of copper and steel are 385 J s−1 K−1 m−1 and 50 J s−1 K−1 m−1 respectively. The…2022 · Q175 · MCQ
  16. Three vessels of equal capacity have gases at the same temperature and pressure. The first vessel contains helium (monoatomic), the second contains fluorine (diatomic) and the third contains sulfur hexafluoride (polyatomic). The correct…2022 · Q181 · MCQ
  17. An ideal gas undergoes four different processes from the same initial state as shown in the figure below. Those processes are adiabatic, isothermal, isobaric and isochoric. The curve which represents the adiabatic process among 1, 2, 3 and… Includes diagram2022 · Q127 · MCQ
  18. The volume occupied by the molecules contained in 4.5 kg water at STP, if the intermolecular forces vanish away is2022 · Q169 · MCQ
  19. A cup of coffee cools from 90∘C to 80∘C in t minutes, when the room temperature is 20∘C. The time taken by a similar cup of coffee to cool from 80∘C to 60∘C at a room temperature same at 20∘C is :2021 · Q153 · MCQ
  20. Match Column - I and Column - II and choose the correct match from the given choices. Includes table2021 · Q159 · MCQ
  21. The average thermal energy for a mono-atomic gas is : (kB is Boltzmann constant and T absolute temperature)2020 · Q129 · MCQ
  22. The mean free path for a gas, with molecular diameter d and number density n can be expressed as :2020 · Q137 · MCQ
  23. A cylinder contains hydrogen gas at pressure 249 kPa and temperature 27∘C Its density is : (R = 8.3 J mol-1 K-1)2020 · Q138 · MCQ
  24. The quantities of heat required to raise the temperature of two solid copper spheres of radii r1 and r2 (r1 = 1.5r2) through 1 K are in the ratio :2020 · Q148 · MCQ
  25. Two cylinders A and B of equal capacity are connected to each other via a stop cock. A contains an ideal gas at standard temperature and pressure. B is completely evacuated. The entire systems is thermally insulated. The stop cock is…2020 · Q157 · MCQ
  26. In which of the following processes, heat is neither absorbed nor released by a system?2019 · Q141 · MCQ
  27. Increase in tempertaure of a gas filled in a container would lead to :2019 · Q147 · MCQ
  28. At what temperature will the rms speed of oxygen molecules become just sufficient for escaping from the Earth’s atmosphere? (Given : Mass of oxygen molecule (m) = 2.76 × 10–26 kg, Boltzmann’s constant kB = 1.38 × 10–23 J K–1)2018 · Q129 · MCQ
  29. The efficiency of an ideal heat engine working between the freezing point and boiling point of water, is2018 · Q138 · MCQ
  30. A sample of 0.1 g of water at 100°C and normal pressure (1.013 × 105 N m–2) requires 54 cal of heat energy to convert to steam at 100°C. If the volume of the steam produced is 167.1 cc, the change in internal energy of the sample, is2018 · Q150 · MCQ
  31. The volume (V) of a monatomic gas varies with its temperature (T), as shown in the graph. The ratio of work done by the gas, to the heat absorbed by it, when it undergoes a change from state A to state B, is Includes diagram2018 · Q151 · MCQ
  32. Thermodynamic processes are indicated in the following diagram. Match the following Includes table Includes diagram2017 · Q158 · MCQ
  33. A gas mixture consists of 2 moles of O2 and 4 moles of Ar at temperature T. Neglecting all vibrational modes, the total internal energy of the system is2017 · Q159 · MCQ
  34. A carnot engine having an efficiency of 101​ as heat engine, is used as a refrigerator. If the work done on the system is 10 J, the amount of energy absorbed from the reservoir at lower temperature is2017 · Q160 · MCQ
  35. A gas is compressed isothermally to half its initial volume. The same gas is compressed separately through an adiabatic process until its volume is again reduced to half. Then2016 · Q155 · MCQ
  36. The molecules of a given mass of a gas have r.m.s. velocity of 2000 m s−1 at 27oC and 1.0 × 105 N m−2 pressure. When the temperature and pressure of the gas are respectively, 127oC and 0.05 × 105 N m−2, the r.m.s.…2016 · Q156 · MCQ
  37. A refrigerator works between 4oC and 30oC. It is required to remove 600 calories of heat every second in order to keep the temperature of the refrigerated space constant. The power required is (Take 1 cal = 4.2 Joules)2016 · Q157 · MCQ
  38. One mole of an ideal monatomic gas undergoes a process described by the equation PV3 = constant. The heat capacity of the gas during this process is2016 · Q155 · MCQ
  39. The temperature inside a refrigerator is t2 oC. The amount of heat delivered to the room for each joule of electrical energy consumed ideally will be2016 · Q156 · MCQ
  40. A given sample of an ideal gas occupies a volume V at a pressure P and absolute temperature T. The mass of each molecule of the gas is m. Which of the following gives the density of the gas ?2016 · Q157 · MCQ
  41. An ideal gas is compressed to half its initial volume by means of several processes. Which of the process results in the maximum work done on the gas ?2015 · Q146 · MCQ
  42. The coefficient of performance of a refrigerator is 5. If the temperature inside freezer is −20oC, the temperature of the surroundings to which it rejects heat is2015 · Q147 · MCQ
  43. Two vessels separately contain two ideal gases A and B at the same temperature, the pressure of A being twice that of B. Under such conditions, the density of A is found to be 1.5 times the density of B. The ratio of molecular weight of A…2015 · Q148 · MCQ
  44. A Carnot engine, having an efficiency of as heat engine, is used as a refrigerator. If the work done on the system is 10 J, the amount of energy absorbed from the reservoir at lower temperature is2015 · Q151 · MCQ
  45. The ratio of the specific heats Cv​Cp​​=γ in terms of degrees of freedom (n) is given by2015 · Q152 · MCQ
  46. Figure below shows two paths that may be taken by a gas to go from a state A to a state C. In process AB, 400 J of heat is added to the system and in process BC, 100 J of heat is added to the system. The heat absorbed by the system in the… Includes diagram2015 · Q153 · MCQ
  47. One mole of an ideal diatomic gas undergoes a transition from A to B along a path AB as shown in the figure. The change in internal energy of the gas during the transition is Includes diagram2015 · Q154 · MCQ
  48. A monatomic gas at a pressure P, having a volume V expands isothermally to a volume 2V and then adiabatically to a volume 16V. The final pressure of the gas is (Take γ = 5/3)2014 · Q154 · MCQ
  49. A thermodynamic system undergoes cyclic process ABCDA as shown in figure. The work done by the system in the cycle is Includes diagram2014 · Q155 · MCQ
  50. The mean free path of molecules of a gas, (radius r) is inversely proportional to2014 · Q156 · MCQ
  51. Which of the following relations does not give the equation of an adiabatic process, where terms have their usual meaning?2013 · Q158 · MCQ
  52. A system is taken from state a to state c by two paths adc and abc as shown in the figure. The internal energy at a is Ua​=10J. Along the path adc the amount of heat absorbed dQ1 = 50 J and the work obtained dW1 = 20 J whereas… Includes diagram2013 · Q159 · MCQ
  53. Two Carnot engines A and B are operated in series. The engine A receives heat from the source at temperature T1 and rejects the heat to the sink at temperature T. The second engine B receives the heat at temperature T and rejects to its…2013 · Q160 · MCQ
  54. In a vessel, the gas is at pressure P. If the mass of all the molecules is halved and their speed is doubled, then the resultant pressure will be2013 · Q161 · MCQ
  55. The amount of heat energy required to raise the temperature of 1 g of Helium at NTP, from T1K to T2K is2013 · Q155 · MCQ
  56. During an adiabatic process, the pressure of a gas is found to be proportional to the cube of its temperature. The ratio of Cp​Cp​​ for the gas is2013 · Q156 · MCQ
  57. In the given (V − T) diagram, what is the relation between pressure P1 and P2? Includes diagram2013 · Q157 · MCQ
  58. A gas is taken through the cycle A → B → C → A, as shown. what is the net work done by the gas? Includes diagram2013 · Q158 · MCQ
  59. An ideal gas goes from state A to state B via three different processes as indicated in the P-V diagram. If Q1, Q2, Q3 indicate the heat absorbed by the gas along the three processes and ΔU1, ΔU2, ΔU3 indicate the… Includes diagram2012 · Q97 · MCQ
  60. One mole of an ideal gas goes from an initial state A to final state B via two processes : It first undergoes isothermal expansion from volume V to 3V and then its volume is reduced from 3V to V at constant pressure. The correct P-V…2012 · Q167 · MCQ
  61. A thermodynamic system is taken through the cycle ABCD as shown in figure. Heat rejected by the gas during the cycle is Includes diagram2012 · Q168 · MCQ
  62. A mass of diatomic gas (γ=1.4) at a pressure of 2 atmospheres is compressed adiabatically so that its temperature rises from 27oC to 927oC. The pressure of the gas in the final state is2011 · Q100 · MCQ
  63. During an isothermal expansion, a confined ideal gas does − 150 J of work against its surroundings. This implies that2011 · Q157 · MCQ
  64. When 1 kg of ice at 0oC melts to water at 0oC, the resulting change in its entropy, taking latent heat of ice to be 80 cal/oC, is2011 · Q158 · MCQ
  65. A monatomic gas at pressure P1 and volume V1 is compressed adiabatically to 81​th of its original volume. What is the final pressure of the gas?2010 · Q90 · MCQ
  66. If cp and cv denote the specific heats (per unit mass of an ideal gas of molecular weight M, then2010 · Q91 · MCQ
  67. If ΔU and ΔW represent the increase in internal energy and work done by the system respectively in a thermodynamical process, which of the following is true ?2010 · Q180 · MCQ
  68. The internal energy change in a system that has absorbed 2 kcal of heat and done 500 J of work is2009 · Q167 · MCQ
  69. In thermodynamic processes which of the following statements is not true ?2009 · Q168 · MCQ
  70. At 10oC the value of the density of a fixed mass of an ideal gas divided by it pressure is x. At 110oC this ratio is2008 · Q158 · MCQ
  71. If Q, E and W denote respectively the heat added, change in internal energy and the work done in a closed cyclic process, then2008 · Q159 · MCQ
  72. An engine has an efficiency of 1/6. When the temperature of sink is reduced by 62oC, its efficiency is doubled. Temperatures of the source is2007 · Q142 · MCQ
  73. A Carnot engine whose sink is at 300 K has an efficiency of 40%. By how much should the temperature of source be increased so as to increase its efficiency by 50% of original efficiency ?2006 · Q165 · MCQ
  74. The molar specific heat at constant pressure of an ideal gas is (7/2) R. The ratio of specific heat at constant pressure to that at constant volume is2006 · Q166 · MCQ
  75. An ideal gas heat engine operates in Carnot cycle between 227oC and 127oC. It absorbs 6 × 104 cal of heat at higher temperature. Amount of heat converted to work is2005 · Q166 · MCQ
  76. Which of the following processes is reversible?2005 · Q167 · MCQ
  77. The equation of state for 5 g of oxygen at a pressure P and temperature T, when occupying a volume V, will be (where R is the gas constant)2004 · Q154 · MCQ
  78. One mole of an ideal gas at an initial temperature of T K does 6R joule of work adiabatically. If the ratio of specific heats of this gas at constant pressure and at constant volume is 5/3, the final temperature of gas will be2004 · Q155 · MCQ
  79. An ideal gas heat engine operates in a Carnot cycle between 227oC and 127oC. It absorbs 6 kcal at the height temperature. The amount of heat (in kcal) converted into work is equal to2003 · Q166 · MCQ
  80. The efficiency of Carnot engine is 50% and temperature of sink is 500 K. If temperature of source is kept constant and its efficiency raised to 60%, then the required temperature of sink will be2002 · Q166 · MCQ
  81. A scientist says that the efficiency of his heat engine which work at source temperature 127oC and sink temperature 27oC is 26%, then2001 · Q162 · MCQ
  82. To find out degree of freedom, the expansion is2000 · Q159 · MCQ
  83. The (W/Q) of a Carnot engine is 1/6, now the temperature of sink is reduced by 62oC, then this ratio becomes twice, therefore the initial temperature of the sink and source are respectively2000 · Q160 · MCQ