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Astro 203, Section 1, Spring 2002, March 6, Olszewski and Bailin
There's one best answer to each question. Fill out the Scantron in pencil.

1) For what is Henrietta Leavitt reknowned?
   a) Cepheid Period-Luminosity relation
   b) Stellar classification
   c) Spectra of different stars ``look different'' because of temperature
      effects
   d) Stars are mostly Hydrogen
   e) both c and d

2) For what is Cecilia Payne-Gaposchkin reknowned?
   a) Cepheid Period-Luminosity relation
   b) Stellar classification
   c) Spectra of different stars ``look different'' because of temperature
      effects
   d) Stars are mostly Hydrogen
   e) both c and d

3) For what is Annie Jump Cannon reknowned?
   a) Cepheid Period-Luminosity relation
   b) Stellar classification
   c) Spectra of different stars ``look different'' because of temperature
      effects
   d) Stars are mostly Hydrogen
   e) both c and d

4) When Hertzsprung and Russell made their H-R diagram, what properties of stars
   were plotted?

   a) H versus R, where H is Planck's constant and R is the perfect gas constant.
   b) Absolute magnitude versus spectral type
   c) Mass versus spectral type
   d) Mass versus luminosity
   e) Mass versus temperature

5) Two stars have the same temperature. They have different APPARENT magnitudes.
   What can you conclude about their relative sizes?
   a) Nothing.
   b) The star with the brighter apparent magnitude is the larger of the two.
   c) They have the same size.
   d) Nothing. But you can conclude that the one with the brigher apparent
      magnitude is the farther away of the two.

6) Two stars have the same temperature. They have very different ABSOLUTE
   magnitudes. What can you conclude about their relative sizes?
   a) Nothing.
   b) The star with the brighter absolute magnitude is the larger of the two.
   c) They have the same size.
   d) Nothing. But you can conclude that the one with the brigher absolute
      magnitude is the farther away of the two.

7) Why is the center of the Sun a good place for fusion reactions?
  a) It's hot and dense there.
  b) There's lots of hydrogen nuclei there.
  c) both a and b.
  d) There are lots of neutrinos there to start the reaction.
  e) none of the above.






8) How do we know that the main sequence is a mass sequence?
  a) We have measured the masses of many main-sequence stars by using
     the laws of gravity on binary stars.
  b) We know it's a temperature sequence, therefore it must be a mass sequence.
  c) We know that the red giant region is not a mass sequence, so the main
     sequence must be.
  d) It has to do with rates of nuclear fusion reactions.

9) The equation   L = 4  R  T , called the Stefan-Boltzman Law, is
   especially useful to astronomers in conjunction with the H-R diagram
   because
   a) If we know L and T for a star, we can derive R, the radius of the star.
   b) If we know L and T for a star, we can derive R, the distance to that star.
   c) We then know the wavelength at which most of the stellar light is emitted.
   d) It tells us that fusion is occurring in the center of the star.

10) If I conclude, from some measurement, that a star is a main-sequence star 
    with the temperature of the Sun, what deduction can I immediately make.
   a) That star is actually a red giant.
   b) That star has the same luminosity as the Sun.
   c) That star is at the same distance as the Sun.
   d) That star is much smaller than the Sun.