Astronomy II (Astr 1020)
Spring 2008
Prof Richard Ignace
HOMEWORK #2
Notes:
You will need a calculator, a pencil, and a standard scantron.
Each question has one correct answer. Choose the best answer for each. Mark your answer on the scantron.
This homework is due at the beginning of class on February 12. Late homeworks will not be accepted.
1. Wien’s law describes
a) how color depends on temperature.
b) how energy depends on frequency.
c) how brightness depends on temperature.
d) how orbital period depends on orbital size.
e) how the force of gravity depends on mass and separation.
2. The Stefan-Boltzmann law describes
a) how color depends on temperature.
b) how energy depends on frequency.
c) how brightness depends on temperature.
d) how orbital period depends on orbital size.
e) how the force of gravity depends on mass and separation.
3. A blackbody is
a) a perfect reflector.
b) a perfect emitter.
c) a perfect tan.
d) a perfect absorber.
e) light before it passes through a prism.
4. A beam of light originally emitted at 8000 ˚
A is measured at 8002 ˚
A owing to the Doppler shift. What
is the percent change in the wavelength?
a) 2.5%
b) 0.25%
c) 0.025%
d) 0.0025%
1
