Solid-State Physics Quiz

What are phonons in the context of solid-state physics?

• Elementary excitations representing atomic lattice vibrations

• Particles that carry electric charge

• Atoms in a crystal lattice

• None of the above

What characterizes acoustic phonons?

• High-frequency vibrations

• Low-frequency vibrations where atoms move in-phase

• Vibrations that do not carry energy

• None of the above

What is the significance of the phonon dispersion relation?

• It describes how the frequency of a phonon depends on its wave vector

• It shows the energy of a phonon is constant

• It indicates that phonons do not interact with electrons

• None of the above

What does the Free Electron Theory explain?

• The behavior of conduction electrons in metals

• The properties of insulators

• The structure of atomic nuclei

• None of the above

What is the Fermi energy?

• The maximum energy that electrons can have at absolute zero

• The energy of phonons at room temperature

• The energy required to remove an electron from an atom

• None of the above

How does the Drude model describe electrical conductivity?

• As a function of electron density and relaxation time

• As a constant value for all materials

• As dependent only on temperature

• None of the above

What is the primary cause of electrical resistance in metals at temperatures above absolute zero?

• Scattering of electrons by phonons

• Scattering of electrons by impurities

• The absence of free electrons

• None of the above

What role do phonons play in superconductivity?

• They mediate the attractive interaction between electrons

• They increase electrical resistance

• They have no effect on superconductivity

• None of the above

What is the difference between classical and quantum models of electron behavior?

• Classical models use Maxwell-Boltzmann statistics, while quantum models use Fermi-Dirac statistics

• Quantum models predict higher heat capacities than classical models

• Both models are identical in their predictions

• None of the above

What does the Sommerfeld model correct in the classical prediction of heat capacity?

• It accounts for only electrons near the Fermi surface contributing to heat capacity

• It states that all electrons contribute equally

• It eliminates the concept of heat capacity

• None of the above