2. In convection, heat transfer coefficient depends on? A. Fluid velocity B. Thermal conductivity of fluid C. Both A and B D. None
3. Which of the following does not require a medium for heat transfer? A. Conduction B. Convection C. Radiation D. All require medium
4. Temperature is a measure of: A. Entropy B. Internal energy C. Average kinetic energy of particles D. Heat content
7. PV=nRT is derived from A. Newton's laws B. First law of thermodynamics C. Kinetic theory of gases D. Second law of thermodynamics
8. The root mean square speed of gas molecules is proportional to A. Absolute temperature B. Pressure C. Molar mass of gas D. Number of molecules
9. Heat capacity at constant volume is A. Greater than at constant pressure B. Equal to constant pressure C. Less than constant pressure D. Zero
10. What is the effect of surface roughness on radiation? A. No effect B. Increases emissivity C. Decreases emissivity D. Random effect
11. Which of the following affects the rate of radiation? A. Surface temperature B. Surface color C. Both A and B D. None
13. Which thermometer works on principle of thermal expansion of liquids? A. Gas thermometer B. Mercury thermometer C. Platinum resistance thermometer D. Bimetallic strip
14. Heat gained by water = heat lost by metal in calorimeter is based on: A. First law of motion B. Conservation of momentum C. Newton’s law D. Conservation of energy
15. Maximum error in temperature measurement is least for: A. Mercury thermometer B. Gas thermometer C. Alcohol thermometer D. Bimetallic thermometer
16. The kinetic energy of a molecule depends on A. Mass only B. Velocity only C. Temperature only D. Temperature and mass
18. The effusion rate of gas is inversely proportional to A. Square root of density B. Square root of molar mass C. Pressure D. Volume
19. Heat required to raise temperature of 1 kg water by 1°C: A. Specific heat of water B. Calorimeter constant C. Latent heat of fusion D. Latent heat of vaporization
20. Heat gained = Heat lost is used in problems assuming: A. All of these B. Perfect conduction C. No temperature gradient D. No heat loss
21. Internal energy change in isothermal process A. Zero B. Positive C. Negative D. Depends on volume
22. Volume of a liquid increases on heating due to: A. Density decrease B. Viscosity increase C. Pressure increase D. Thermal expansion
23. Biot number is the ratio of? A. Convection to conduction B. Conduction to convection C. Radiation to convection D. Conduction to radiation
24. Linear expansion is directly proportional to: A. Original length B. Temperature change C. Material property D. All of these
25. Thermodynamic efficiency of Carnot engine depends on A. Source temperature B. Sink temperature C. Both source and sink temperatures D. Working substance
26. Temperature is measured in Celsius and Fahrenheit. Relation is: A. F = C + 32 B. F = 9/5 C + 32 C. F = 5/9 C + 32 D. F = 32 − 9/5 C
27. Area expansion coefficient β is related to linear expansion α by: A. β = α² B. β = 2α C. β = α/2 D. β = √α
28. Kirchhoff’s law of thermal radiation relates? A. Absorptivity and emissivity B. Reflectivity and transmissivity C. Conductivity and emissivity D. Convective coefficient
29. For steady conduction in a slab, the temperature distribution is? A. Linear B. Exponential C. Logarithmic D. Random
30. A bimetallic strip bends due to: A. Different coefficients of expansion B. Same coefficients of expansion C. External force D. Temperature decrease
31. Which gas law can be derived from kinetic theory of gases? A. Boyle’s law B. Charles’s law C. Avogadro’s law D. All of the above
32. At absolute zero, the kinetic energy of gas molecules is A. Zero B. Non-zero C. Infinite D. Depends on pressure
33. Relative humidity decreases if: A. Moisture increases B. Moisture decreases C. Air temperature decreases D. Air temperature increases
34. Heat exchanger effectiveness is defined as? A. Actual/Maximum possible heat transfer B. Maximum/Actual C. Heat lost/Heat gained D. None
35. Latent heat of vaporization of water (L_v) at 100°C: A. 4200 J/kg B. 2260 kJ/kg C. 334 kJ/kg D. 540 J/kg
36. Apparent expansion formula is: A. ΔV_apparent = ΔV_liquid − ΔV_container B. ΔV_apparent = ΔV_container − ΔV_liquid C. ΔV_apparent = ΔV_liquid / ΔV_container D. ΔV_apparent = ΔV_liquid + ΔV_container
37. What is the thermal resistivity of a material? A. Inverse of thermal conductivity B. Same as thermal conductivity C. Difference of thermal conductivity D. Product of conductivity and thickness
38. If 2 moles of gas at 300K expand to double volume isothermally, work done is A. R*T*ln2 B. 2*R*T*ln2 C. R*T/2 D. 2*R*T
40. Heat required to raise 100 g of water from 20°C to 80°C (c=4.2 J/g°C) is: A. 25.2 kJ B. 4200 J C. 252 J D. 4.2 kJ
43. Which expression gives radiative heat transfer between surfaces? A. q = σAT^4 B. q = kAΔT/L C. q = hAΔT D. q = mCpΔT
45. Stefan-Boltzmann law applies to? A. Black bodies B. All surfaces C. Only metals D. Only insulators
46. Root mean square speed is always A. Greater than average speed B. Less than average speed C. Equal to average speed D. Cannot determine
47. Linear expansion is proportional to: A. Material B. Temperature change C. Original length D. All of these
48. Phase change without temperature change is called: A. Sensible heat change B. Latent heat change C. Specific heat change D. Heat capacity change