XII Physics Thermodynamics Online Test Mdcat-2024

1. Superficial expansion is the extension in:

2. A heat engine absorbs 100J of heat, simultaneously 20J of work is done on the system then the internal energy:

3. “It is impossible to flow heat from cold body to hot body without expenditure of energy” this is :

4. Value of Boltzmann’s constant:

5. The unit of molar-specific heat is the same as that of

6. During melting of ice, its entropy:

7. The ratio of the specific heat of a gas at constant volume to its specific heat at constant pressure is:

8. Which of the following is NOT a state variable?

9. According to the second law of thermodynamics:

10. A Carnot heat engine operates between 400K and 500K. Its efficiency is:

11. The maximum theoretical efficiency of a Carnot heat engine operating between reservoirs at the steam point and at room temperature is about:

12. Thermodynamics process in which there is maximum loss of energy:

13. Concept of entropy is defined by:

14. Concept of internal energy is defined by:

15. Four students found set of Cp and Cv (in cal/deg mole) as given below. Which of the following set is correct?

16. If two system X and Y are in thermal equilibrium. If X is heated at constant volume and Y is heated at constant pressure, and again finally maintained at thermal equilibrium, then heat Q given to the systems X and Y and internal energy U stored in the systems X and Y are:

17. If Cv= 5/2 R, then Cp will be:

18. A Carnot engine whose sink is at a temperature of 300K has an efficiency of 45%. By how much should the temperature of source:

19. An ideal gas undergoes an expansion in volume from 1.3 × 10 m³ to 3.9 × 10 m³ at a constant pressure of 1.3 × 10 Pa. During this expansion, 24 J of heat is supplied to the gas. What is the overall change in the internal energy of the gas?

20. Temperature is a property, which determines:

21. Heat capacity of source in carnot engine is:

22. A Carnot engine at working at temperatures of 520K and 140 K, is percent efficient for:

23. A Carnot engine works between two temperatures of 800 °C and 150 °C, its efficiency would be:

24. A Carnot engine works between 300K and 600K having an output of 800 J per cycle. What is the amount of heat energy supplied to the engine from the source per cycle?

25. A cycle tyre bursts suddenly. It is an example of:

26. In adiabatic expansion:

27. Entropy is called as “Time Arrow” because the entropy of the universe:

28. Ratio of W(isothermal) vs W(adiabatic) for same expansion:

29. 300 g of water requires 30000 J of thermal energy to raise the temperature from 25 °C to 85 °C, the heat capacity of the water is:

30. There would be maximum entropy change when carnot engine is delivered at:

31. The process in which the temperature varies suddenly is called:

32. If Cv value for any gas is two times the gas constant, then its Cp value would be:

33. The relationship between Celsius and Fahrenheit scales temperature is:

34. During fever, doctor tells he/she has fever at 105 degrees, it is temperature of:

35. Ratio of rms speed of N₂ and O₂ at the temperatures of 50 °F is:

36. At same temperature, rms speed of lightest gases He and H would be:

37. A quantity of an ideal gas is compressed to half its initial volume. The process may be adiabatic, isothermal, or isobaric. Rank those three processes in order of the work required from least to greatest:

38. The pressures p and volumes V of five ideal gases, with the same number of molecules, are given below. Which has the highest temperature?

a) p = 1 × 10⁵ Pa and V = 1 dm³

b) p = 3 × 10² KPa and V = 6 dm³

c) p = 4 × 10³ Pa and V = 4 cm³

d) p = 6 × 10² MPa and V = 2 mm³

39. Root mean velocity is related to temperature as:

40. A sample of an ideal gas is compressed by a piston from 10 m³ to 5 m³ and simultaneously cooled from 273◦ C to 0◦ C. As a result, there is:

41. Celsius scale at which both Fahrenheit and Kelvin show the same reading:

42. Heat capacity of any substance at its melting point and boiling point:

43. Units of coefficients of linear expansion and volume expansion:

a. mm/C° , mm³/C°
b. m/C° , m³/C°
c. 1/C° , 1/C°³
d. 1/C° , 1/C°

44. When a annular ring of aluminum is heated:

45. Press(iron) works on the principal of:

46. Both the Celsius scale and the Fahrenheit scale show the same reading at a condition, now condition is changed and the Celsius temperature rised up to 20 degrees then the temperature on the Fahrenheit scale
would be:

47. Kelvin scale coincide with Fahrenheit scale at a temperature of:

48. Substances used in thermometer:

49. When two objects are in thermal equilibrium with each other then they:

50. According to KMT, at the same temperature, all gases have: