Q 9
I am measuring the spectrum of the stars in a spectroscopic binary system. When one of the stars is moving toward the Earth in its orbit, we observe
A) that the lines in its spectrum get brighter
B) that the lines in its spectrum merge with the lines of the other star
C) that it is no longer possible to learn what elements are in the star
D) that the lines in its spectrum show a blue-shift
E) none of the above
Q 10
Which law do astronomers use to determine the masses of the stars in a spectroscopic binary system?
A) Wien's Law
B) Kepler's Third Law
C) Stefan-Boltzmann Law
D) Hubble's Law
E) Jenny Craig's Law
Q 11
Stars that do not have what it takes to succeed as a star (i.e. do not have enough mass to fuse hydrogen into helium at their centers) are called:
A) extras
B) red giants
C) spectroscopic stars
D) brown dwarfs
E) main sequence stars
