2011 Homeworks

HW #1

An essay about "Physics and Me".

HW #2

Examine units of energy and their relationships (converting rule), at least including J, eV, kcal, K, 1/cm, and nm.

HW #3 (Relativity)

Example 2.3

Problem 21

HW #4 (Diffraction)

Derive the below equations:

1. d sin(theta) = n x lambda (constructive interference) for Young's double slit experiment

2. 2d sin(theta) = n x lambda (constructive interference) for diffraction from crystals

HW #5 (XRD vs. ED)

Discuss about similarities/differences and good/bad of XRD vs. ED techniques. You also have to answer why the ED is used for microscopy techniques (TEM and SEM), but the XRD is not.

HW #6 (H psi = E psi)

1. Solve 1-D Shrodinger equations of the particle-in-a-box and the simple harmonic oscillator problems. (solve: energy and wavefunctions)

2. Discuss similarity and difference between two groud-state wavefunctions.

HW #7 (s, p, d, f)

1. Sketch s, p, d, and f orbitals.

2. Sketch the 4s orbitals.

HW #8 (O2 singlet-triplet)

Sketch molecular orbitals and their electronic occupation of triplet and singlet O2.

HW #9 (Crystal structure)

1. Find and draw lattice vectors of 2D-square, 2D-hexagonal, and 3D-FCC, BCC, SC, HCP lattices.

2. Discuss lattice vectors and bases of graphene and diamond carbon.

HW #10 (BZ)

1. Draw the first Brillouin zones of the 2D square and hexagonal lattices.

2. What are the lattice and reciprocal lattice vectors of diamond Si?

HW #11(Phnon and DOS)

1. Discuss the relationship between the umklapp process of phonon scattering and thermal conductivity.

2. Draw schematically the density of states of 0D, 1D, 2D, and 3D electron gas.

HW #12 (band gap)

1. Explain why some solids exhibit metallic, semiconducting, or insulating character in electrical conductivity.

2. Comment about the class or what you feel about physics now.