Download Astronomy 100—Quiz 4

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Astronomy 100—Quiz 4
Prof. Mo
INSTRUCTIONS: Write your name and ID number on BOTH this sheet and the computer grading form.
Choose the letter of the response that you think best answers the question.
Use a #2 Pencil on the computer grading form. Be careful to match up your question number with the
number on the computer form, and thoroughly erase all changed answers and stray marks on the form.
1. Harlow Shapley used globular cluster to show that the
A. Milky Way is just one of many ”island universes”.
B. Solar System is located far from the center of the Milky Way.
C. Solar System is located near the center of the Milky Way.
D. Milky Way is actually a globular cluster itself.
E. Milky Way is not much bigger than the Solar System.
2. Most of the mass of the Milky Way galaxy is
A. contained in the massive O and B stars in the galaxy.
B. contained in the H I regions of the galaxy.
C. contained in the H II regions of the galaxy.
D. contained in the dark matter halo of the galaxy.
E. contained in the disk of the galaxy.
3. Which of the following statements about our Milky Way Galaxy is incorrect?
A. It is a spiral galaxy.
B. It consists of both a disk and a halo of stars.
C. The Sun is at a distance of about 25,000 light years from the galactic center.
D. New stars are being formed from the gas in the disk.
E. none of the above.
4. Young star clusters
A. are found in the halo of our galaxy.
B. only form in the bulge of the galaxy.
C. form mostly in the gaseous disk of the Galaxy.
D. are found only in elliptical galaxies.
E. contain only metal poor stars.
5. Which of the following is a characteristic of the disk component of the Milky Way?
A. random stellar orbits.
C. young stars.
E. all above except A.
B. circular stellar orbits.
D. active star formation regions.
6. Old stars contain less amount of heavy elements because
A. old stars destroy heavy elements as they age.
B. old stars burn their nuclear fuels faster.
C. heavy elements haven’t had time to settle to the core of these old stars.
D. older stars are made from gas that is contaminated by fewer previous generations of stars.
E. all of those.
7. Which of the following delicious objects most closely resembles the general shape of our visible galaxy?
A. fried egg.
C. cantaloupe.
E. Milky Way candy bar.
B. apple.
D. French fry.
8. The rotation curve of a galaxy can be used to determine
A. the relative number of hot young stars in the galaxy.
B. the relative amount of gas and dust in the galaxy.
C. the radius of the galaxy.
D. the luminosity of the galaxy.
E. the mass of the galaxy.
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9. Choose the one with the least amount of gas or dust in the following:
A. Spiral galaxies.
C. Elliptical galaxies.
B. The Milky Way
D. Barred Spiral galaxies.
E. Irregular galaxies.
10. Astronomers use Cepheid variable stars to measure galaxies’ distances because
A. the faster they vary, the more distance they are.
B. their luminosity can be determined from their period of variation.
C. they obey Hubble’s Law.
D. they are the most common type of main-sequence star variable in galaxies.
E. they all lie in the same spot on the HR diagram.
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Key for Quiz4
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B
D
E
C
E
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D
A
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B