Star and Typical Lithium Element
Homework #2 1. How many electrons would a typical neon element have? How many electrons does a typical lithium element have? Use that information to qualitatively describe the difference between the emission spectrum of neon and lithium.
10, 3, the greater the number of electrons the greater the number of emission lines on the spectrum
2. The dominant element present in the star’s spectrum to the right:
Hydrogen
3. Is a toaster oven filament an example of an emission, absorption, or continuous spectrum? What about a neon lamp?
Continuous Spectrum, Emission
4. Add and remove a gas cloud, and change to Telescope 2 and back to Telescope 1. Just an exercise, no question.
5. Now have the star recede (so that it is moving away from Earth). Are the absorption lines shifted to the red or to the blue? Now have the star move perpendicular to Earth. In this case, is the absorption lines shifted to the red or to the blue?
Red, No change in the absorption lines getting absorbed by Earth.
6. How would you expect an absorption line to look in a star that is rapidly rotating? Why? Feel free to draw an illustration if that helps.
The absorption line of the side of the star spinning towards you would be blue while the absorption line of the side of the star spinning away from you would be red. The absorption line in the middle between these would look the same as if the star was not rotating. This is due to Rotational Doppler Broadening. This will cause a broadened spectral
10, 3, the greater the number of electrons the greater the number of emission lines on the spectrum
2. The dominant element present in the star’s spectrum to the right:
Hydrogen
3. Is a toaster oven filament an example of an emission, absorption, or continuous spectrum? What about a neon lamp?
Continuous Spectrum, Emission
4. Add and remove a gas cloud, and change to Telescope 2 and back to Telescope 1. Just an exercise, no question.
5. Now have the star recede (so that it is moving away from Earth). Are the absorption lines shifted to the red or to the blue? Now have the star move perpendicular to Earth. In this case, is the absorption lines shifted to the red or to the blue?
Red, No change in the absorption lines getting absorbed by Earth.
6. How would you expect an absorption line to look in a star that is rapidly rotating? Why? Feel free to draw an illustration if that helps.
The absorption line of the side of the star spinning towards you would be blue while the absorption line of the side of the star spinning away from you would be red. The absorption line in the middle between these would look the same as if the star was not rotating. This is due to Rotational Doppler Broadening. This will cause a broadened spectral