Review Notes for Exam 2

You should be familiar with the topics listed below. You should also review the Learning Objectives distributed in class. It is an absolute certainty that you will see questions on Kirchhoff's laws of spectroscopy, the H-R diagram, and the proton-proton cycle on the exam. Know them—together they will account for about 30% of the total points on the exam. No kidding.

  1. The Scientific Method (537kB pdf)
  2. The General Theory of Relativity
    1. The principle of equivalence
    2. Gravity as curvature of spacetime
    3. Gravitational waves and the "speed of gravity"
  3. The Electromagnetic Spectrum
    1. Wave-particle duality of EM radiation
    2. The relationship between energy, wavelength, and frequency of EM radiation
    3. The Doppler effect
  4. Blackbodies
    1. Wien's displacement law and the Stefan-Boltzmann law
    2. Kirchhoff’s laws of spectroscopy
    3. Stellar spectra and their classification
    4. The relationship between luminosity, radius, and effective (i.e. surface) temperature of stars
    5. The spectrum of hydrogen (specifically, the Balmer series) and how it is produced
  5. Distance determinations
    1. Apparent magnitude vs. absolute magnitude
    2. Trigonometric parallax
    3. The distance modulus (see Variable Stars in M15 lab)
  6. The Hertzsprung-Russell diagram
  7. The Sun
    1. The solar interior and mechanisms of energy flow transport
    2. The proton-proton cycle
    3. The Sun's visible features: sunspots, flares, prominences, coronal mass ejections
    4. Properties of the solar atmosphere: photosphere, chomrosphere, transition region and corona
  8. Post-main sequence evolution of a Sun-like star
    1. Core hydrogen depletion and electron degeneracy
    2. Helium flash, triple alpha process, and red giant phase
    3. Helium depletion, red supergiant phase and helium shell flashes, instability and planetary nebula formation
    4. Chandrasekhar limit, white dwarfs and electron degeneracy
  9. Post-main sequence evolution of a very massive star
    1. Production of heavy nuclei (including significance of formation of iron-56)
    2. Core collapse, rebound, shockwave restart and supernova
    3. Neutron degeneracy and creation of neutron star

Exam 2 Sample Questions

To help you prepare for the style of questions I often ask, here are a few sample questions to solve:

  1. What is the triple-alpha process and when does it occur in the life of a star?
  2. Sketch a diagram or describe the atmospheric layers of the Sun.
  3. Explain why sunspots are darker than the surrounding photosphere.

Solutions to Sample Questions