# Black hole thermodynamics: Quiz

Question 1: The laws of black hole mechanics are expressed in ________.
Natural unitsPlanck unitsGeometrized unit systemStoney scale units

Question 2: Stating that κ cannot go to zero is analogous to the third law of thermodynamics which, in its weak formulation, states that it is impossible to reach ________ temperature in a physical process.
CarbonAbsolute zeroEntropyThermodynamic temperature

Question 3: Starting from theorems proved by ________, Jacob Bekenstein conjectured that the black hole entropy was proportional to the area of its event horizon divided by the Planck area.
Roger PenroseStephen HawkingAnthony James LeggettJohn Archibald Wheeler

Question 4: If black holes carried no entropy, it would be possible to violate the ________ by throwing mass into the black hole.
Second law of thermodynamicsExergyHistory of thermodynamicsGibbs free energy

Question 5: The four laws of black hole mechanics are physical properties that ________ are believed to satisfy.
Schwarzschild metricBlack holeKerr–Newman metricKerr metric

Question 6: Using the ________ relationship between energy, temperature and entropy, Hawking was able to confirm Bekenstein's conjecture and fix the constant of proportionality at 1/4:
ThermodynamicsThermodynamic equationsStatistical mechanicsPhysics

Question 7: Though not yet fully understood in general, the holographic principle is central to theories like the ________.
Kaluza–Klein theoryString theoryAdS/CFT correspondenceQuantum field theory

Question 8: Analogously, the first law of thermodynamics is a statement of ________, which contains on its right hand side the term T dS.
Sustainable energyBiofuelEnergy conservationSustainable transport

Question 9: Analogously, the second law of thermodynamics states that the ________ of an isolated system is a non-decreasing function of time, suggesting a link between entropy and the area of a black hole horizon.
Gibbs free energyEntropyIdeal gas lawStatistical mechanics

Question 10: Later, Hawking showed that black holes emit thermal ________ corresponding to a certain temperature (Hawking temperature).