Ast 220 Study Guide for Chapter 5
1. Understand the following terms: emitted light, absorbed light, transmitted light,
reflected (or scattered) light, photon, wavelength, frequency, gamma rays, x-rays,
ultraviolet light, visible light, infrared light, radio waves, emission line spectrum,
continuous spectrum, absorption spectrum, thermal radiation, Doppler effect, red shift,
and blue shift.
2. Understand that light is a form of radiative energy that can act as a particle and a wave.
3. Understand that the energy and color of light is determined by its frequency.
4. Understand that white light is made up of a mixture of many different colors of light.
5. Understand and be able to identify the frequencies of light that are below and above
the range of frequencies that make up the part of the spectrum that is visible to the human
eye.
6. Understand the basic structure of atoms and molecules and how isotopes of a given
element are different.
7. Understand that energy is absorbed or released from an atom in the form of photons of
a specific set of frequencies (or wavelengths) characteristic of the type of atom.
8. Understand how emission, continuous, and absorption spectra are produced and how
they help give us information about the composition and temperature of stars and gas
clouds.
9. Understand how the Doppler effect works and how it provides information about how
celestial objects are moving.
10. Understand how the Doppler effect can tell us if and how an object is rotating.
