Aim to answer every question before checking. Missed questions point you to the sections you need most.
1. (3.1) Which temperature scale sets zero at absolute zero?
C. Kelvin is the SI absolute temperature scale. Use K for all thermodynamic formulas involving T.
2. (3.1) To convert °C to K:
B. Only an offset, no scaling; sizes of degree C and K are identical.
3. (3.2) The zeroth law of thermodynamics states:
A. Justifies the use of thermometers: the thermometer is the third system.
4. (3.2) Thermal equilibrium between two objects means:
D. Fundamental definition of temperature.
5. (3.3) The three modes of heat transfer are:
C. Conduction through solids; convection through fluids; radiation through vacuum (EM waves).
6. (3.3) Heat conduction rate through a solid depends on:
B. This is Fourier's law of heat conduction.
7. (3.4) Heat required to change a mass m by ΔT is:
A. Water has c ≈ 4.18 J/g·°C, one of the highest of any common substance.
8. (3.4) A material with a higher specific heat:
D. Water's high c moderates ocean and body temperatures against rapid fluctuations.
9. (3.5) Linear thermal expansion of a rod of original length L₀ and temperature change ΔT is:
C. Volumetric expansion has a coefficient 3α for isotropic materials.
10. (3.5) Water is unusual among common substances because:
B. Why ice floats and lakes freeze from the top down, preserving aquatic life below.
11. (3.6) During a phase change (e.g., ice → water at 0 °C):
A. Q = m × L, where L is the latent heat of the transition.
12. (3.6) The latent heat of vaporization of water is:
D. The big number is why sweating cools you so effectively: lots of heat is carried off per gram of evaporated water.
13. (3.7) The first law of thermodynamics is:
C. Sign conventions: Q is positive when heat flows into the system; W is positive when the system does work on its surroundings.
14. (3.7) For a gas, the "work done by the gas":
B. For non-isobaric processes, W = ∫P dV (the area under a P-V curve).
15. (3.8) On a P-V diagram:
A. A closed loop on a PV diagram encloses the net work per cycle; clockwise loop = engine (positive net work out); counterclockwise = refrigerator.
16. (3.8) In an isobaric process:
D. Heating a gas inside a piston at constant atmospheric pressure is a classic isobaric example.
17. (3.9) An isothermal process:
A. Requires thermal contact with a reservoir that absorbs or supplies heat during the process.
18. (3.9) An adiabatic process:
B. Rapid processes (fast compression/expansion) approximate adiabatic because there is no time for heat exchange.
19. (3.10) The second law of thermodynamics states:
A. Forbids perpetual motion machines of the second kind (extracting work from a single heat reservoir).
20. (3.10) Entropy is a measure of:
D. Intuitively, gases have the highest entropy; pure crystalline solids at 0 K have the lowest (S = 0 by the third law).
21. (3.11) For a reversible process, entropy change is:
A. For irreversible processes, compute ΔS using an equivalent reversible path connecting the same states.
22. (3.11) The entropy of the universe:
B. The "arrow of time" at the macroscopic scale is entropy's one-way march upward.
23. (3.12) Carnot's theorem states:
A. Thermodynamic ceiling on heat-engine efficiency, independent of working substance.
24. (3.13) A phase diagram:
D. Above the critical point, the distinction between liquid and gas disappears (supercritical fluid).
